[ /yir^^7 J 3 ^* vv^ ^' -^ ^ * - V— ^ miam ' I — - jrt jE i^P ^ _y ^^ K . ^P ^^.^K^' ^n ^hi^ -^-^^^K~^^^^ ^V" ~ ^i ■^ J ~ ^K' f-f-* ^M~~ ' hS HTjiC-'^* ^ ^J~^ ^' Z "JT 1 t I' X" Y» - > ■ V . ,7 ^ /^ ^— ^ ^'ia ^S V«4 ^^^p:5 — ^^ ^"^^^KV - ^ JS? ^1^1 ^^'1 Wt^ .^.^a^ |j&J^^g • ~^lm * ^^H ' ' A 1 ' ^': 1 >S1 ":^m. AH^c^B^B^ /^Vl ^^^ " ""^= J. ^ __ Uf^ ~^^ f-i ^*> ; A • ^^ ' v^ :' j'i: • 1' C * 3l ' f ' :M ^ SS^'^ ~ ^ ^ ^ A*' ^^' V ^ iMiit ^Bif^^yim^^ ss*^^ '\'i ' ^'V' V Cf^rd^^ ^^ 1 ^5 *■ '2 ^'^ *— V . Ih^h-Ml^ i-i 4 :• / i'' f/f9^ % 1 hB-ifSTiZr^r—^^s i- ^ == > :k / p — 'i^^ Sk.; a. * « ^.^^H^ ^ ^\^m ir^* ^^ F— Y " 23 *p- J: ' »C C^ w BflSSfi-^ ^ BEtr^JSs, ^ - i =?^^l — i ;^ ^ ■«J^^^_ t'. It- ^«— ^-^ T V fc- ^S*^-- — ' f ,r-j— ^ 'iww^^sAsas l^ I < yd £*- .' «iirii^m^«pt ^■■b ^^<<~'^^^KKk < < c t^/' / f imk _i "i IS bf^i r « « met' t^™'"^- Fig. 15. Eit'iocolletis gemin^tella; a, larva; h, pupa (enlarged three tunes), loc, Fig. l(i. P.ncoulatrix pomifoliella. Fig. 17. Colcophora; larva. Fig. 18. Evonetia saccatell:) ; 18(7, larva; 18 fi, case (enlarged). Fig. 10. Eithocolletis nidificansella (enlarged); 19 «, cocoon. Fig. 20. Aglo«sa cnprealis. Fig. 21. Anclivlopev.n v.Tooininna. Fig. 22. Penthina vitivovam renlarared). Fig. 23. Pteropliorus periscelidactylus; o, larva; b, pupa (enlarged three times). GUIDE TO THE STUDY OF INSECTS. THE CLASS OF INSECTS. That brancli of the Animal Kingdom known as the Ar- THROPODA, includes all animals having the body composed of rings or segments, like short cylinders, which are placed suc- cessively one behind the other, and which bear jointed appen- dages, or feet. The plan of their entire organization, the es- sential features which separate them from all other animals, lies in the idea of articulation, the apparent joinitig together of distinct body-segments, bearing hard, jointed appendages. If we observe carefully the body of a Worm, Ave shall see that it consists of a long cylindrical sac, which at regular intervals is folded in upon itself, thus giving a ringed (nnnulated, or articulated) appearance to the body. In Crustaceans (crabs, lobsters, etc.) and in Insects, from the deposition in the skin of the latter of a peculiar chemical substance called chitine, the walls of the body become so hard- ened, that when the animal is dead and dry, it readily breaks into numerous very perfect rino-s. Though this branch contains a far gieater number of species than any other of the animal kingdom, its myr- iad forms can all be reduced to a simple, ideal, ty^tical figure ; that of a long slender cylinder, divided into numerous segments, arranged in two or, as in Insects, into three regions, and bearing jointed appendages. It Fig. i. is by the unequal development and the various modes of group- ing the rings, as well as the differences in their number, and also in the changes of form of their appendages, i.e., the feet, jaws, and antennas, that the various forms of Arthrojyoda are pro- duced. The Cuvierian branch ArtUmlata comprise the modern branches of Worms and Arthropods. Fig. 1, Worm-like larva of a Fly, Scenopiuus.—Orujinal. 1 2 THE CLASS OF INSECTS. Fig. 2.* Artliropoclous animals are also very distinctly hdateral^ i.e the botiy is symmetrically divided into two lateral halves, and not only the trnnk bnt the limbs also show this bilateral symmetry. In a less marked degree there is also an antero- j)osterior symmetry^ i.e. each end of the body is opposed, just as each side of the body is, to the other.* The line separating the two ends is, however, imaginary and vague. The autennse, on the anterior pole, or head, are represented by the caudal, or anal, stylets (Fig. 2), and the single parts on the median line of the body corre- spond. Tlius the labrum and clypeus are represented by the tergite of the eleventh segment of the abdomen. In nearly allWorms (Fig. 3) the long, tubular, alimentary canal occupies the centre of the body ; above it lies the "heart," or dorsal vessel, and below, upon the under side, rests the nervous system. be d The breathing apparatus, or "lungs," in Worms consists of f\ simple filaments, placed on the front of the head ; or of gill-like processes, as in the Crustaceans, which are formed by membran- ous expansions of the legs ; or, " pjg. 3. ^ as in the Insects (Fig. 4), of delicate tubes (tracheae), which * Professor Wyman (On Symmetry and Homology in Limbs, Proceedings of the Boston Society of Natural History, liSGT) has shown that antero-posterior symmetry is very marked in Articulates. In the adjoining figure of ./cera (Fig. 2) the longi- tudinal lines illustrate what is meant by bilateral symmetry, and the transverse lines "fore and aft" symmetry. The two antero-posterior halves of the body are very symmetrical in the Crustacean genera Jiera. Onisciis, Porcellio, and other Crustacea, and also among the M.vriopods, Scutigera, Polydesmus, " in which the limbs are repeated oppositely, though with different degrees of inequality, from the centre of the body backwards and forwards." "Leuckait and Van Beneden have shown that JMysis has an ear in the last segment, and Schmidt has described an eye in the same part in a worm, Amplncora." — From Wyman. Fiu. Z represents an ideal section of a Worm. / indicates the skin, or nius- cuhir body-wall, which on each side is i)roduced into one or more fleshy tubercles, usually tipped with bristles or hairs, which serve as organs of locomotion, and THE CLASS or INSECTS. ramify throughout the whole interior of the animal, and con- n?ct with breathing pores (stigmata) in the sides of the body. They do not breathe tln-ougli the mouth as do the higher ani- mals. The trachcEe and blood-vessels follow closely the same Fig. 4. course, so that the aeration of the blood goes on, apparently, over the whole interior of the body, not being confined to a single region, as in the lungs of the vertebrate animals. Thus it is by observing the general form of the body-walls, and the situation of tlie different anatomical systems, both in relation to themselves and the walls of the body, or crust, which surrounds and protects the more delicate organs Avit'.iin, that we are able to find satisfactory characters for isolating, in our definitious, the Artliropoda from all other animals. We shall peiceive more clearly the differences between tlie two branches of articulated or jointed animals, namely, the Worms and tlie Arthropoda, by examining their yonng often as lungs. The nervous cord (,n) rests on the floor of the cj'hnder, sending a filament into the oar-like feet (/), and also around the intestine or stomach (t), to a supi)lcmentary cord {d), which is situated just over the intestine, and under th3 heart or dorsal vessel (c). The circle c and e is a diagram of the circulatory sys- tem; c is the dorsal vessel, or heart, from the side of which, in each ring, a small vessel is sent downwards and around to e, the ventral vessel. — Orir/innl. Fig. 4. An ideal section of a Bee. Here the crust is dense and thick, to which strong muscles arc attached. On the upper side of the ring tlic wings grow out, while the legs are inserted near the under side. The tracheaa (d) enter through the stir/ma, or breathing i)ore, situated just under the wing, and their branches sul)- divideand are distributed to the wings, with their live piiucipal veins as indicated THE CLASS OF INSECTS. Fiic. 5. stages, from the time of tlioir exclusion from the egg, until they p:iss into mature life. A more careful study of this l^eriod than we ai-e now able to enter upon would show us how much alike the young of all Arthropods are at first, and how soon tliey begin to difter, and assume the shape characteristic of their branch. Most Worms, after leaving the egg, are at first like some infusoria, being little sac-like animalcules, often ciliated over nearly the entire surface of the infinitesimal body. Soon this sac-like body grows longer, and con- tracts at intervals ; the intervening parts become unequally enlarged, some segments, or rings, formed b}^ the contraction of the body-walls, greatly exceeding in size those next to them ; and it thus assumes the appearance of being more or less equally ringed, ^, as in the young Terebella (Fig. 5), wdiere the ciliix^ are restricted to a single circle surrounding the body. Gradually (Fig. G) the cilia? disap- pear and regular locomotive organs, consisting of minute paddles, grow out from each side ; feelers (antenuie), jaws, and eyes (simple rudi- mentary eyes) appear on the few front rings of the body, which are grouped by themselves I into a sort of head, though it is difficult, in a large proportion of the lower worms, for un- skilled observers to distinguish the head from the tail. Thus we see throughout the growth of the worm, no attempt at subdividing the body into regions, each endowed Avith its peculiar I ^functions ; but only a more perfect system of . ' rings, each relatively very equally developed, in the figure, also to the dorsal vessel (c), the intestine (6), and the nervous cord (a). The tracheie and a nervous lilameut are also sent into the legs and to the wings. The tracheie are also distrihuted to the dorsal vessel and intestine by numerous bi'anches which serve to hold them in place. — Original. Fig. .'). Young Tercheila, .soon alter leavmg the eg^. — From A. Af/assiz. Fi(i. (i repre.-^ents the oinl>ryo of a worm (Autolijlus corniitu.-!) at :i later stage ol' growth, n is the middle tentacle of tlie head ; c, one of tlie posterior tentacles; /), the two eye-spots at the base of the huider pair of feelers; c is one of a row of car-like organs {cirri) at the base of which are inserted the locomotive bristles, THE CLASS OF INSECTS. 5 but all becoming respectively more complicated. For example, in the P2arth-worm {Lumbricus) , each ring is distinguishable into iin upper and under side, and in addition to these a well- marked side-area, to which, as for example in marine worms (e. g. Nereis), oar-like organs are attached. In most worms eye-spots appear on the front rings, and slender tentacles grow out, and a pair of nerve-knots (ganglia) are apportioned to eacli ring. In the Crustaceans, such as the fresh-water Crawfish {^iy.td- cus), as shown by the German naturalist Kathke; and also in the earliest stages of the Insect, the body at once assinncs a worm-like form, thus beginning its embr3'0nic life from the goal reached by the adult worm. The young of all Crustaceans (Fig. 7) first begin life in the egg as oblong flattened worm-like bodies, each end of the body being alike. The young of the lower Crustaceans, such as the Barnacles, and some marine forms (Copepoda), and some lowly organized parasitic species inhabiting the gills of fishes, are hatched as microscopic cmbr^'os which would readily be mistaken for young mites (Acarina). In the higher Crus- taceans, such as the fresh-water Crawfish, the young, when hatched, does not greatly differ from the i)arent, as it has passed through the worm-like stage within the egg. Fig. 7 represents the young of the fresh- water Lobster (Crawfish) before leaving the egg. The body is divided into rings, ending in lobes on the sides, which are the rudiments of the limbs, b is the rudiment of the ej'e- stalk, at the end of which is the eye ; a is the fore antennae ; c is the hind antenna? ; d is one of the maxilla-feet ; e is the first pair of true feet destined in the adult to form the large ''claw." Thus the eye-stalks, antenna, claws, and legs are moulded upon a common form, and at first are scarcely distin- with the cirri serving as swimming' and locomotive organs; rf, the candal styles, or tail-foelers. In this figure we see how slight are the difl'erences between the feelers of the head, the oar-like swimming organs, and the candal filaments; we can easily see that they are but modifications o£a common form, and all arise from the common limb-bearing region of the body. The alimentary canal, with tlio proventricnhis, or anterior division of the stomach, occupies the middle of the body; while the mouth opens on the under side of the head. — From A. Agassis. Fig. 7. Embryo of the Crawfish. — From Rathke. 1* 6 THE CLASS OF INSECTfJ. guishable from each other. Here we see the embryo divided into a head-thorax and a tail. It is the same with Insects. Within the egg at the dawn of life they are flattened oblong bodies curved upon the yelk- mass. Before hatching they become more cylindrical, th<> limbs bud out on the sides of the rings, the head is clearly demarked, and the young caterpillar soon steps forth from the egg-shell ready armed and equipped for its riotous life. As will be seen in Fig. 8, the legs, jaws, and antennae are first started as buds from the side of the rings, being simply elongations of the bod3'-waIl. which bud out, become larger, and finally jointed, until the \x buds arising from the thorax or abdomen become legs, those from the base of the head be- come jaws, while the antenme and palpi sprout out from the front rings of the head. Thus while the bodies of all articulates are built up from a common em- bryonic form, their appendages, which are so diverse, when we compare a Lobster's claw with an Insect's antenna, or a Spider's spinneret with the hinder limbs of a Centipede, are yet but modifications of a common form, adapted for the different uses to which they are put by these animals. Fig. 8. A Caddis, or C:ise-11y [Mijatncides] in the ej?g, with part of the yolk {x) not yet in;',losed within tlio body-walls. «, antennre ; between a and h the mandi- bles; I), maxilla; o, lal)ium; r/, the sei)arate eye-spots (ocelli), which aderwards in- crease greatly in nvimbei' and unite to form the compound eye. The "neck" or junction of the head with the thorax is seen at the front part of the yolk-mass; e, the three pairs of legs, which arc folded once on themselves;/, the pair of anal legs attached to the tenth ring of the abdomen, as seen in caterpillars, which form long antenna-like lilanu'nt> in the Cockroach and May-tly, etc. The rings of the body are but partially formed: they are cylindrical, giving the body a worm-like form. Here, as in Ihe other two llgures, though not so distinctly seen, the antennas, jaws, and last pail- of abdominal legs are modifications of but a single form, and grow out from the side of the body. The head-appendages are directed forwards, as they are to be adapted for sensory aniece, or, divided into an epimerum and episteriuun, form a distinct lateral region, on which the stigmata are sit- uated. The segments of the abdomen have received from Lacaze-Duthiers a still more special name, that of iirite, and the different tergal pieces belonging to the several rings, but especially those that have been modified to form the genital armor have been designated by him as tergites. We have applied this last term to the tergal pieces generally. The typi- cal number of abdominal segments is eleven. In the lowest insects, the Neuroptera, there are usually eleven ; as we have counted them in the abdomen of the embryo of Diplax. In others, such as the Hymenoptera and Lepidoptera, there may never be more than ten, so far as present observation teaches us. The formation of the sting, and of the male intromittent organ, may be observed in the full-grown larva and in the in- COMPOSITION OF THE OVIPOSITOR. 15 complete pupa of the Humble-bee, and other thin-skianed Hymenopterous larvoi, and in a less satisfactory Avay in the young Dragon-flies. If the larva of the Humble-bee be taken just after it has become full-fed, and as it is about to enter upon the pupa state, the elements a a o o <:iD,c::> (sterno- rhab- dites Lacaze- Duthiers), or tubercles, destined to Fi-. IG. form the ovipositor, lie in separate pairs, in two groups, Fig. 11. Fig. 15. exposed distinctly to view, as in Figures 14-18. The ovipointor thus consists of three pairs of slender non-articulated tubercles, situated in juxta- position on each side of the mesial line of the body. The first pair arises from the eighth abdominal ring, and the second and third pair grow out from the ninth ring. The ends of the first pair scarcely reach beyond the base of the third pair. AVith the growth of the semi-pupa, the end of the abdomen decreases in size, and is Fig. 14. Rudiments of the sting, or ovipositor, of the Humble-bee. 8, 9, 10, stcruites of cightli, ninth, anil tenth abdominal rings in the larva, a, first pair, .situ- ated on the eighth sternite ; b, second and inner pair ; and f, the outer pair. The let- tering is the same in figures 14-2-2. The inner pair (b), forms the true ovipositor, thiough which the eggs are supposed to pass when laid by the insect, the two outer pairs, a and o, sheathing the inner pair. Ganin sh!)ws tliat in the embryo oi PoIynemuiFig. G.j.5), the throe pairs of tubercles arise from tho 7tli, 8th and 9th s'g- meuts respectively. Fig. 1.5,10. The same a little f.irther advanced. Fig. 17. The three pairs now iippear as if together growing from tho base of the ninth segment; 17n, side view of the same, showing the end of the abdomen grow- mg smaller through the diminution in size of the under side of the body. Fig. 18. The three pairs of rhabdites now nearly equal in size, and nearly ready to unite and form a tube; ISa, side view of the same; the end of the abdo- men still more pointed; the ovipositor is situated between the seventh and tenth rings, and ia partially retracted within the body. 18 a. 16 THE CLASS OF INSECTS. gradually incurved toward the base (Fig. 18), and the three pairs of rhabdites approach each other so closely that the two outer ones completely ensheath the inner, until a complete extensible tube is formed, which is gradually withdrawn entirely within the body. The male genital organ is originally composed of three pairs (two pairs, apparently, in yEs- .^ clma., Fig. 19) of tubercles all arising from the ninth abdominal ring, being sternal outgrowths and placed on each side of the f-~Trsr-\ mesial line of the body, two be- i" 's '-'^■ v_kLLy iiig anterior, and very unequal in size, and the Fig. 19. third pair nearer the base of the abdomen. The ex- ternal genital organs are to be considered as probably homologous with the limbs, as Ganin has shown that they bud out in the r.amc manner from (sec p. 704 ..a fig. G55) the artliromere* ■^ Tins view will apply to the ¥W. 21. genital armor of all Insects, so far as we have been able to observe. It is so in the pupa of u-Eschna (Fig. 21), and the pupa of Agrion (Fig. 22), which com- pletely repeats, in its essential features, the structure of the ovipositor of Bombus. Thus in ^schna and Agrion the ovipositor consists of a pair of closely appressed ensi- form processes which grow out from under the posterior edge of the eighth abdominal ring, and are embraced between two pairs *This term is proposed as better defining the ideal ring, or primary zoological element of an articulated animal than the terms snmite or ^ouiiite, which seem too vague; we also propose the term arthroderm for the outer crust, or body walls, of Articulates, and arthropleura for the pleural, or limb-bearing region, of the bod}-, benig that portion of tlie artliromere situated between the tevgite and sternite. Fiu. 19. The rudiments of the male introniittent organ of the pujia of ^Eschna, consisting of two llattened tubercles situated on the nmth ring; the outer pair large and rounded inclosing tlie smaller linear oval pair. Fig. 20. The same in the Humble-bee, but consisting of three pairs of tubercles, X, y, z ; 8, 9, 10, the last three segments of the abdomen. Fig. 21. The rudimentary ovipositor of the pupa of yEsclma, a Dragon-fly. Fig. 22. The same in pupa of Agrion., a small Dragon-fly. Here the rudiments of the eleventh abdominal ring are seen, d, the base of one of the abilominal false gills. The ovipositor of Cicada is formed in the same way. — Figs. H-23 original. Fig. 22. COIPOSITION OF THE OVIPOSITOK. 17 of thin lamolliform pieces of similir form and structure, arising from the sternite of the ninth ring. These outgrovvtlis appar- ently also homologizG with the filiform, antennae-like, jointed appendages of the eleventh ring, as seen in the Perlidse and most JSeuroptcra and Orthoptera (especially in Mantis tes- sellata where they (Fig. 23) closely resemble antennae), which, arising as they do from the arthropleural, or limb- [ --, L bearing region of the bod}^, i. e. between Fig. 23. the sternum and episternum, are strictly homologous Avith the abdominal legs of the Myriapoda, the "false legs" of cater- pillars, and the abdominal legs of some Xeuropterous larvse {ConjdaUs^ Phryganeidce, etc.). It will thus be seen that the attenuated form of the tip is produced by the decrease in size of certain parts, the actual disappearance of others, and the perfection of tliose parts to be of future use. Thus towards the extremity of the body the pleurites are absorbed and disappear, the tergites overlap on the sternites, and the latter diminish in size and are withdrawn within the body, while the last, or eleventh sternite, entirely disappears.* Meanwhile the sting grows larger and larger, until finally we have the neatly fashioned abdominal tip of the bee concealing the complex sting with its intricate s^'stem of A'isceral ves- sels and glands. The ovipositor, or sting, of all insects, therefore, is formed on a common plan (Fig. 24). The solid elements of the arthro- *In lianafro, however, Lacaze-Dutliiers hns noticed the curious fact that in order to form the long respiratory tube of this insect, the tergite and sternite of the prcgeuital (eighth) segment are aborted, Avhile the ideurites are enonnously en- larged and elongated, so as to carry the stigmata far out to the end of the long tube thus formed. Fig. 23. End of the abdomen of Mantis tenKellata ; p, many-jointed anal style resembling an antenna. 5-11, the last seven abdominal segments; the S-llth ster- nite.s being obsolete. — From Lacaze-Duthiers. Fig. 21. Ideal plan of the structui-e of the ovipositor in the adult insect. i-7t, the tergites, connected by dotted lines ■with their coi-responding sternites. b, the eighth tergite, or anal scale ; c, epinierum ; a, a, two pieces forming the outer pair of rliabdites; i, the second pair, or stylets; and /, the inner pair, or sting; d, the 18 THE CLASS OF INSECTS. mere are modified to form the parts supporting the sting alone. The external opening of the oviduct is always situated between the eighth and nintli segments, while the anal opening lies at the end of the eleventh ring. 80 that there are really, as Laca/ce-Duthiers observes, tlu'ee segments interposed between the genital and anal openings. The various modifications of the ovipositor and male organ will be noticed under the different suborders. The Structure of the Head. After studying the com- position of the thorax and abdomen, where the constituent parts of the elemental ring occur in their greatest simjjlicity, we may attempt to unravel the intricate structure of the head. We are to determine whether it is composed of one, or more, segments, and if several, to ascertain how many, and then to learn what parts of the typical arthromere are most largely developed as compared with the development of similar parts in the thorax or abdomen. In this, perhaps the most difficult problem the entomologist has to deal with, the study of the head of the adult insect alone is only guesswork. "We must trace its growth in the embryo. Though many writers consider the head as consisting of but a single segment, the most emi- nent entomologists have agreed that the head of insects is com- posed of two or more segments. Savigny led the way to these discoveries in transcendental entomology by stating that the appendages of the head are but modified limbs, and homol- ogous with the legs. This view at once gave a clue to the complicated structure of the head. If the antennae and biting organs are modified limbs, then there must be an elemental segment present in some form, however slightly developed in the mature insect, to which such limbs are attached. But the best observers have differed as to the supposed number of such theoretical segments. Burmeister believed that there were two only ; Carus and Audouin thought there were three ; ^IcLeay and Newman four, and Straus-Durckheim recognized seven. From the study of the semipupa of the Humble-bee (Bombics) Biipport of the sting; e, the support of the stylet (i). 7?, the anus ; O, the outlet of the oviduct. The seventh, eighth, and ninth sternites are aborted. — From Lacazt- Duthiers, THE STRUCTURE OF THE HEAD. 19 and several low Neuropterous forms, as the larva of Ephemera^ but chiefly the embryos of Diplax^ Chri/sopa, Attelabuft, Nema- tus, and Palex, we have concluded that there are four such ele- mental segments in the head of hexapodous insects. On reference to fig. 57 it will be seen that tliere is a sternal portion on the under side of the two posterior segments of the head, and in the embr^'o of Attelahns we have seen sterna also developed in the antennal and mandibular segments, so that we may conclude that there are four segments in the head of all SIX footed insects, correspou ling to the jointed appendages, I, e. the labium, or second maxilhie, the first maxilhe, the man dibles, and the antennae. Though having, in accordance with the generally received opinions of Milne-Edwards, Dana, and others, believed that the eyes of Crustacea, and therefore of Insects, were the homologues of the limbs, and developed on separate segments placed in front of the antennal segment, as stated in the previous editions of this work ; I have, however, on farther study of the subject, been led to reconsider the mat- tar, and decide that the eyes are but modified dermal sense cells, and in certain articulates developed on limb-bearing seg- ments. Thus in the King Crab (Limidus) a pair of ocelli are situated on the fii'st segment of the body, and the large com- pound eyes grow out on the back of the third segment, both bearing limbs. In the embryos of all the insects yet exam- ined, the eyes are groups of specialized cells of the skin which grow out on the upper, or tergal, side of the same segment which bears the antennaa. In certain mites, as Hydrachna, and its allies, the simple eyes are situated over the second pair of legs, and at a considerable distance behind the head. Among the worms, also, organs of sight, as in Pohjoplithalmus^ are developed on each segment of the body ; or, as in certain Pla- narians, scattered irregularly over the body. The three ocelli, when present, are developed after the eyes Appear. Each of these three ocelli is situated upon a distinct piece ; but we must consider the anterior single ocellus as in reality formed of two, since in the immature pupa of Bombus the anterior ocellus is transversely ovate, resulting from the fusion of two originally distinct ocelli. There are, therefore, apparently two pairs of ocelli. The clypeus and labrum are 20 THE CLASS OF INSECTS. simply a fcld of the skin of the front part of the antennary segment, and are not to be compared with the tergite or rudi- ment of the eleventh segment of the abdomen. Now, since the arthropleural is the limb-bearing region in the thorax, it must follow that this region is quite well devel- oped in tlie head, while the tergal region, bearing the organs of sight, sometimes of enormous size, is perhaps still more largely developed ; and as all the parts of the head are subordinated in their development to that of the appendages of which they form the support, it must follow logically that the larger por- tion of the body of the head is jyleiiral and tergal, and that the s'ternal parts are very slightly developed. Thus each region of the body is characterized by the relative development of the three parts of the arthromere. In the abdomen the upper (tergal) and under (sternal) surfaces are most equally devel- oped, while the pleural line is reduced to a minimum. In the thorax the pleural region is much more developed, either quite as much, or often more than the ujjper, or tergal portion, Avhile the sternal is reduced to a minimum. In the head the tergites form the main bulk of the region, and the sternites are reduced to a minimum. Tablk ok thk Segments of the Head and their Appendages, lieginning with the jiost anterior. First Sesrment [Anteiinarij), Second Segment ( Mandibular), Third Segment {First Maxillary), Fourth Segment ( Second Maxillary, or) Labial), Preorul. V Tergal, Pastoral . i Pleural, ^ Pleural, ^Tergal (occiput), > Pleural (genu), 5 Sterual (gula), AntennfB, together with the labrum, epipharynx, clypeus, eyes, aud ocelli. Mandibles. First maxillae. Second maxillaa (Lalnuni). The Appendages. We naturally begin with the thoracic appendages, or legs, of which there is a pair to each ring. The leg (Fig. 25) consists of six joints, the basal one, the coxa, in the Hymenoptera, Lcpidoptera, and Diptera, consisting of t^YO THE APPENDAGES. 21 pieces, i.e. the coxa and trochcmtine (see Fig. 12); the tro- chanter; the femiir; the tibia, and, lasth', the tarsus, which is subdivided into from one to five joints, tlie latter being qa the normal number. The terminal joint ends in a pair ^ of claws between which is a cushion-like sucker called the pulviUus. This sucking disk enables the Fly to walk upside down and on glass. In the larva, the feet are short and horny, and the Fig. 25. joints can be still distinguished. In IMyriopods, each segment of the abdomen has a pair of feet like the thoracic ones. "We must consider the three pairs of spinnerets of Spiders, which are one to three-jointed, as homologous with the jointed limbs of the higher insects. In the six-footed insects (Hexapoda), the abdominal legs are deciduous, being present in the Coleopterous grub, the Dipterous maggot, the caterpillar, and larva of the Saw-fly, but disappearing in the pupa state. They are often, as in most maggots, eitlier absent, or reduced in number to the two anal, or terminal pair of legs ; while in the Saw-flies, there are as many as eight pairs. These "false" or "prop-legs" are soft and flesh}^, and without articulations. At the retrac- tile extremity is a crown of hooks, as seen in caterpillars or the hind-legs of the larva of Chirononms (Fig. 26), in which the prothoracic pair of legs is reduced to inarticu- late fleshy legs like tlie abdominal ones. The jwsition of the different pairs of legs deserves notice in connection with the principle of " antero-posterior symmetry." The fore- legs are directed forw^ards like the human arms, ^^s- 26. but the two hinder pairs are directed backwards. In the Spiders, three pairs of abdominal legs (spinnerets) are retained through- out life ; in the lower Ilexapods, a single pair, which is ap- pended to the eleventh segment, is often retained, but under a form which is rather like an antenna, than limb-like. In some Neuropterous larvae {Phryganea, Corydahis, etc.) the anal pair of limbs are very well marked ; they constitute the "anal forceps" of the adult insect. They sometimes become true, manj^-jointed appendages, and are then remarkably like Fig. 25. A, coxa; B, trochanter; C, femur; D, tibia; F, tibial spurs ; E, tarsus, divided into five tarsal joints, the fllth ending m a claw. — /'Voj/i Sanborn. 22 THE CLASS OF INSECTS. antennoe, as in the instance of Mantis tessellata described by Lacaze-Duthiers (Fig. 23). In the Cockroach these append- ages, sometimes called "anal cerci," resemble the antennie of the same insect. In the Lepidoptera and Hymenoptera they do not api)ear to be jointed, and are greatl}^ aborted. The Wings. The wings of insects Ih'st appear as little soft vascular sacs permeated by tracheae. They grow out in the preparatory stages (Fig. 27) of the pupa from the side of the J. thorax and above the insertion of the legs, i.e. between the epimerum and .»« tergum. During the pupa state they are pad-like, but when the pupa skin is thrown off they expand with air, and in a few minutes, as in the Butterfly, enlarge to many times their original size. The wings of insects, then, are simple expansions of the crust, spread over a framework of horny tubes. These tubes are really double, consist- ing of a central trachea, or air tube, '"' "'■ inclosed within a larger tube filled with blood, and which performs the functions of the Acins. Hence the aeration of the blood is carried on in the wings, and thus they serve the double purpose of lungs and organs of flight. The number and situation of these veins and their branches (veinlets) are of great use in separating genera and species. The typical number of primary veins is five. They diverge outward at a slight angle from the insertion of the wing, and are soon divided into veinlets, from which cross veins are thrown out connecting with others to form a net-work of veins and veinlets, called the venation of the wing (Figs. 28, 29). The interspaces between the veins and veinlets are called cells. At a casual glance the venation seems very irregular, but in many insects is simple enough to enable us to trace and name the veinlets. The five main veins, most usually present, are Fig. 27. The semipnpa of Bomhus, the larva skin havinjr been removed, show ing the two pairs of rudimontary wings growing ont from the mesothorax (/,•), uni , metathovax (m). n and the seven sncceeding dots represent the eight abdominal stigmata, the first one (m) being in the pnpa situated on the thorax, since the flrsj ring of the abdomen is in this stage joined to the thorax. — Original. THE WINGS. 23 Fig. 28. called, beginning at the costa, or front edge, the costal^ subcostal, median, submedian, and internal, and sometimes the median divides into two, making six veins. The costal vein is un- divided ; the subcostal and me- dian are divided into several branches, while the submedian and internal are usually simple. The venation of the fore- wings affords excellent marks in se2:)arating genera, but that of the hind wings varies less, and is consequently of less use. The wings of many insects are divided by the veins into three well-marked areas ; the costal, median, and iriternal. The costal area (Fig. 31 &) forms the front edge of the wing and is the strongest, since the veins are nearer together than elsewhere, and thus afford the greatest resistance to the air Fig. 28. Fore and hind wings of a Butterfly, showing the venation. I. fore wing: «, costal vein; b, subcostal vein; ^i, b2, b:'., b*, bo, live subcostal veinlets; c, inde- pendent vein (it is sometimes a branch of tlie subcostal, and sometimes of the me- dian vein) ; fl, median vein ; di, d2, ,is, di, four median veinlets ; e, submedian vein ; /, internal vein; h, interno-meduin veinlet (rarely found, according to Doubleday, except in Papilloand Morpho); b and r/ are situated m the "discal cell; " ^1, n- tracted at each motion of the wings, as in birds and other ani- mals, and becomes fixe. 3»4. t The brain of inse^'ts is fomieil of several pairs of ganglia, corresponding, probably, to the number of primitive segments composing the head. The nc rroas conl is thus, in the head, massed together and eompacteil to form a brain. Fig. 43, Servous System of Co-rydalHS eontutus. a, ■'cerebrum;'' b, "cere- brelhim ;^ c. thoracic ganglia, which distribute a nerve to each leg: d. eight pairs of abdominal ganglia. The dotted lines represent the wrings. — Frcn Lfi. 'y. 3 Fig.ti. The under or eternal 34 THE CLASS OF INSECTS. close approximation to them." Newport also believes that the ganglionless upper, or internal, column of fibres is analogous to the motor column of Vertebrata, while the external, or under one, corresponds to the sensitive column, thus representing the cerebro-spinal system of the Vertebrata. From each pair of ganglia are distributed special nerves to the various organs. In the larva of Sphinx the normal num- ber of double ganglia is thirteen, and the nervous cord of the Neuroptera and other lowly organized and attenuated forms of insects corresponds in the main to this number. In the adult insect, especially in the Coleoptera, Diptera, Lepidoptera, and Hymenoptera, the three thoracic ganglia are fused together, following the fusion and general headwise development of the segments of the tegument. Besides the central nervous cord, corresponding to the spinal cord of the Vertebrates, there is a vagus, or visceral nerve, representing the sympathetic nerve of higher animals. This nerve "arises, in the larva, from the anterior part of the cerebrum, and, forming a ganglion on the upper sm'face of the pharynx, always passes backward beneath the brain, along the middle line of the oesophagus." In its microscopic structure the nervous cord, like that of Vertebrata, consists of a central "gray" substance, and an outer or periph- eral part, the "white" substance. In the embryo the ganglia are very large and close together, the commissures, or connecting filaments being very short, and small in proportion. Organs of Nutrition. These consist of the alimentary canal and its appendages, or accessory glands (Fig. 44). We have already treated of the external appendages (mouth-parts) which prepare the food for digestion. The simplest form of the alimentary canal is that of a straight tube. In the larva of Stylops and the sedentary young of Bees, it ends in a blind sac, as they live on liquid food and expel no solid excretions. When well developed, as in the adult insect, it becomes a long convoluted thick muscular tube, subdivided into different parts which perform different functions and have distinct names, taken from analogous organs in the vertebrate animals. This digestive tube is composed of three coats, the outer, or j;er/- ORGANS OF NUTRITION. 35 toneal; the middle, or muscular; and the inner, or mucous. The mucous coat is variously modified, being plaited or folded ; or, c d e h f h m n o p J 1 1 9 I Fig. 44. as in the Orthoptera and carnivorous Coleoptera, it is solidified and covered with rows of strong horny teeth, forming a sort of gizzard. The alimentary canal is held in place by retractor muscles, but principally by exceedingly numerous branches of the main tracheae. This canal (Fig. 45) is subdivided into the mouth and pha- rynx, the oisojyhagns, supplementary to which is the crop, or " sucking stomach" of Diptera, Lepidoptera, and Hymenoptera ; the proventriaihis , or gizzard ; the veiUriculus, or true stomach, and tlie intestine, which consists of the ileum, or short intes- FiG. 44. Anatomy of Sphinx ligustri. m, i, q, the nervous cord resting on the floor of the body ; at c, the ganglia fonn a brain-like organ, much larger than the ganglia of the thorax (m) and abdomen {q). From the brain is sent ofl' the euboisophageal nerve which surrounds the gullet into which the food is conveyed by the maxillae, or spiral tongue («), which, when at rest, is rolled up between the -"abial palpi (6). From the nervous cord is also thrown off a pair of nerves to each pair of legs (as at n, o,p) and a branch, d, is sent ofl" from above, distributing nerves to the muscles of flight. The heart, or dorsal vessel (e,/), lies just beneath the median line of the body, and is retained in place by muscular bands (as at /) as well as by small tracheal branches. The alimentary canal (h,j, //), forms a straight tube in the head and thorax; h, the crop, or sucking stomach, which opens into the nesophagus; J, the true, chyle- formmg stomach, which contracts posteriorly, and then dilates near its anal outlet into a cloaca (indicated at ff, but not distinctly, as it is concealed by the numerous urinary vessels). The urinary vessels also indicated at g, form long tubes (which correspond to the kidneys of Vertebrates), opening into the pyloric end of the stomach. The position of the testes {l;)is the same as that of the ovary, and the dotted line I shows the course of the efl'erent duct (vas deferens) and also of the oviduct of the female. The figure represents a longitudinal section of the insect, the legs and ends of the antennae having beea removed. — From Newport. 36 THE CLASS OF INSECTS. tine, and the colon and rectnvi. The latter part, as well as the crop and proventriculus, are sometimes absent. Of the appendages of the canal^ the first are the salivary gkoids, which are usually long simple tubes, which in the larva, ac- cording to Newport, form the silk vessels. They " empty themselves by a single duct tlu'ough the spinneret on the floor (labium) of the mouth." In the Ant-lion {Myrmeleon) the silk is spun from "a slender telescopic- like spinneret, placed at the extremity of its body," and Westwood also states that the larva of Chrysopa spins a cocoon "from the spinneret, at the extremity of the body." These silk glands when taken out of the larva, just as it is about ready to transform, are readily prepared as "gut" for fish-lines, etc., by drying on a board. In the Bees these glands are largely de- veloped to produce a sufiicient amount of salivary fluid to moisten the dry pollen of Fig. 45. flowers, before it enters the oesophagus. "Bee-bread" consists of pollen thus moistened and kneaded by the insect. The Honey-bee also dissolves, by the aid of the salivary fluid, the wax used in making its cells. Newport believes this fluid is alkaline, and forms a solvent for the other- wise brittle wax, as he has seen this insect " reduce the per- fectly transparent thin white scales of newly secreted wax to a pasty or soapy consistence, by kneading it between its man- dibles, and mixing it Avith a fluid from its mouth, before apply- ing it to assist in the formation of part of a new cell." Insects have no true liver; its functions being performed "by the walls of the stomach, the internal tunic of which is composed of closely-aggregated hepatic cells." (Siebold.) In the Spiders and Scorpions, however, there is a liver distinct from the digestive canal. In the Spiders it is very large, enveloping most of the other viscera. Fig. 45. Alimentary tube of Cori/dfilns cornntus. a, oesophagus; h, proven- triculus; c, ventricnlus; , the terminal joint nearly three times as long as the two basal ones. 2, tlie mandibles, and also enlarged, showing the cutting edge divided into four teeth. 3, maxill:i! divided into two lobes: (/, tlie outer and anterior lobe, 2-jiiinted, tlie basal joint terminating in two seta?; and «, the inner lobe concealed from view, in its natural (losition, by the outer lobe, r^ 4, the base or pedicel of the second maxillas, or labium, the expanded terminal portion being drawn sepa- rately; rf and rt, two movable stout styles representing, perhaps, the labial palpi: the lobe to which they are attached is nuiltidentate, and adapted for seizing prey; on the right siile the two styles are appressed to the lobe, x rei)resents, perhaps, the ligula; but we have not yet studied its homologies carefully: this ))art is attached to a transversely linear piece soldered to the main part of the labium, y, the 11th abdominal ring, with its pair of conical anal styles, c, the Just tarsal joint and pair of long slender claws. Fir;. (14. The pui)a of Diplax, having riidiinentarywings, in which the eyes are much larger, and the legs much sliortcr than in the lecently hatched larva; in- troduced to be compared with ihe young larva. Figs. 57-04, oriyiiud. TRANSFORM ATIOXS OF THE INSECT. Gl On review it will be seen how remarkable are the changes in form of the insect before it is hatched, and that all are the resnlt of simple growth. We have seen that the two ends of the body are first formed, and that the under side of the body is formed before the back ; that the bell}'^ is at first turned out- wards, and afterwards the embryo re^'erses its position, the back presenting outwards. All the appendages are at first simple protrusions from the body-walls, and new segments are interpolated near the tip of the abdomen. These changes take place very rapidly, within a very few days, and some of the most important and earlier ones in a few hours. We can now better understand that the larva and pupa stages are the result of a similar mode of growth, though very marked from being in a different medium, the insect having to seek food and act as an independent being. Transformations of the Insect. We have seen that during the growth of the embryo, the insect undergoes remark- able changes of form, the result of simple growth. The meta- morphoses of the animal within the egg are no less marked than those which occur after it has hatched. It will also be seen that the larva and pupa stages are not always fixed, defi- nite states, but only pauses in the development of the insect, concealing beneath the larva and pupa skins the most impor- tant changes of form. The process of hutdiiucj. No other author has so carefully described the process of hatching as Newport, who observed it in the larva of Melos. "When the embryo larva is ready for its change, the egg-shell becomes thinned and concave on that side which covers the ventral surface of the body, but is nuich enlarged, and is more convex on the dorsal, especially towards the head. The shell is then Inu-st longitudinally along the middle of the thoracic segments, and the fissure is ex- tended forwards to the head, which then, together with the thoracic segments, is partially forced through the opening, but is not at once entirely withdi'awn. The antennas parts of the mouth, and legs are still inclosed within separate envelopes, and retain the larva in this covering in the shell. Efforts are then made to detach the posterior segments of the body, which 62 THE CLASS OF INSECTS. are gradually released, and with them the antennae, palpi, and legs, and tlie lar^a removes itself entirely from the shell and membranes. In this process of evolution the young MeJo'e throws off two distinct co\erings : first, the sliell with its lining- membrane, tlie analogue of the membrane in which, as I have elsewhere sliown,* the 3-ouug M^riopod is inclosed, and re- tained several days after tlie bursting of the ovum, and which represents in the Articulata, not the allantois, but npparently the amnion, of Vertebrata ; next, the first, or fa'tal deciduation of the tegument, analogous probably to the first change of skin in the Myrlopod, after it has escaped from the amnion, and also to the first change which the young Arachnidan invariably undergoes a few days after it has left the egg, and before it can take food. This tegument, which, perhai)s, may be analo- gous to the vernix caseosa of Vertebrata, thrown off at the instant of birth, is left by the 3'oung jNIeloe with the amnion in the shell ; and its separation from the body, at this early period, seems necessarj' to fit the insect for the active life it has commenced." (Linn. Trans, xx. p. 30G, etc.) The larva state. The larva (Latin larva^ a mask) was so called because it was thought to mask the form of the perfect insect. The larvae of Butterflies and Moths are called cater- pillars; those of Beetles, <7r;<&s; and those of the two-winged Flies (Diptera) maggots; the larvae of other groups have no distinctive common names. As soon as it is hatched the larva feeds voraciously, as if in anticipation of the coming period of rest, the pupa state, for which stores of fat (the fatty bodies) are dcAeloped for the supply of fat globules out of which the tissues of the new body of the pupa and imago are to be formed. Most larviii moult, or change their skin, four or five times. In the inactive thin-skinned larvae, such as those of Bees, AYasps, and Gall-flies, the moults are not apparent ; as the larva increases in size it out-grows the old skin, which comes off in thin shreds. But in the active larvse, such as cater- pillars, grasshoppers, and grubs, from the rapid absorption of vessels in the outer la3'er of the skin, just before the change, * Philosophical Transactions, Pt. 2, 1841, p. 111. TRANSFORMATIONS OF THE INSECT. 63 7t becomes hard and dry, and too small for the growing in- sect, and is then cast off entire. A series of bee-larvjE can be selected showing a graduation in size and form from the egg and recently hatched larva up to the full-grown larva. In the caterpillar and other active lar^je, there are usually four or five stages, each showing a sudden and marked increase in size. Newport states that the caterpillar of /Sjihinx ligustri moults six times, and at the last moult be- comes a third larger than at any earlier period ; the larva of Arctia caja moults from five to ten times. A few days before the assumption of the pupa state, the larva becomes restless, stops eating, and deserts its food, and usually spins a silken cocoon, or makes one of earth, or chipr., if a borer, and there prepares for the change to the pupa state. During this semipupa period (lasting, in many insects, only for a day or several daj's, but in some Saw-flies through the winter) the skin of the pupa grows beneath that of the quies- cent larva. AVhile the worm-like larva exhibits no trire- gional distinctions, the muscles of the growing pupa contract and enlarge in certain parts so as to modify the larva form, until it gradually assumes the triregional form of the adult insect, with the differentiation of the body into a head, thorax, and abdomen. In a series of careful studies, abundantly illustrated with excellent plates, AVeismann has recently shown that Swammer- dam's idea that the pupa and imago skins were in reality already concealed under that of the larva is partially founded in truth. Swammerdam states, "I can point out in the larva all the limbs of the future nymph, or Culex, concealed beneath the skin," and he also observed beneath the skin of the larvai of bees just before pupating, the antennae, mouth-parts, wings,, and limbs of the adult. (Weismann.) During its transformations the pupa skin is developed from the hypodermis^ or inner layer of skin. This peals off, as it were, from the inner layer of the old larva skin, Avhicli soon dries and hardens, and is thrown off. Meanwhile the muscles of the body contract and change in form, thus causing the origi- nal segments of the larva to infold and contract at certain parts, gradually' producing the pupa form. If, during this period, the 64 THE CLASS OF INSECTS. insect be examined at intervals, a series of slight changes of form may be seen, from tlie larva to the imago state. In soine cases each change is accompanied by a moult, as in the "ac- tive" Ephemera, where Lubbock counted twenty one moults. As a general rule, then, it may l)e stated that the body of the larva is transformed into that of the imago ; ring answer- ing to ring, and limb to limlj in both, the head of the one is homologous with that of the other, and the appendages of the larva are homologous with the ap])endages of the imago. Weismann has shown that in the larva of the Meat-fly, Musca vomitnria, the thorax and head of the imago are developed from what he calls "imaginal disks." These disks are minute isolated portions of the hypodermis, which are formed in the embryo, before it leaves the egg, and are held in place within 'the body-cavity of the larva by being attached either to nerves or tracheae, or both. After the outer layer of the larva skiii dries and hardens, and forms the cask-shaped ptiparhon, the use of which corresponds to the cocoon of moths, etc., these imaginal disks increase in size so as to form the tegumeiit oi' the thorax and head. The abdomen of the Meat-fly, however, is formed by the direct conversion of the eight hinder segments of the body of the larva, into the corresponding f^egments oi the imago. Accompanying this change in the integurricnt there is u destruction of all the larval system of organs ; this is either total or elfected by the gradual destmctlon of tissues. Now we see the use of the "•fatty bortv;" tliis breaks uj), setting free granular globules of fat, winch, p.s Ave have seen in the embryo, produces by the multiplication of cells the new tissues of the pupa. Thus the larva-skin is cast aside, and also the softer organs within, but the formation of new tissues keeps even pace Avith the destruction of the old, and the insect prt ■ serves its identity throughout. The genital glands, however arc indicated even in the embryo, and are gradually develope The insects from these two formations ^ \ '' show a tendency to assume gigantic and '\^ strange shapes. They are also compre- Fig. 08. hensive types, combining the characters of different families and even different suborders. The most re- markable instance is the Eugereon Boecliirtgii Dohrn, from the Coal Formation of Germany. It has been referred by Dr. Hagen, with some doubt, to the Hemiptera, from its long im- mense rostrum into which all the mouth-parts are produced, the labium ensheathing them as usual in the Hemiptera. Its fore- legs are large and raptorial ; but the filiform many-jointed an- tenntie, and the net-veined wings are Ncuropterous characters. Hence Dohrn considers it as a comprehensive type uniting * KXPLANATION OF PLATE 1. Fig. 1. Miamia Brovxonii. A Neiiropterons insect found in iron-stone concre- tions in the Carboniferous beds at Morris, Illinois. The figure is magniiied one- third, and has all its parts restored; the dotted lines indicate the parts not existing on the stone. Reduced from a ligure in tlie Memoirs of tlie Boston Society of Nat- ural History, Vol. I. Fig. 2. Archimulftcris Acadica. AViug of a Cockroach observed by Mr. Barnes in the coal-formation of Nova Scotia. Fig. 3. Platephemera antiqua. A gigantic May-fly obtained by Mr. Hartt in the Devonian rocks of New Brunswick. Fig. 4. Xylobius siyillaria:. The Myriopod (or Gally-worm) found in tlie eoal- formatiou of Nova Scotia, by J. W. Dawson. Copied from a flgurc in Dr. Dawson's Air-breathers of the Coal-period. Magnified. Fig. 5. Lithentomuvi Jlin-fii. A Ncuropterous insect, the specimen first dis- covered by Mr. Hartt in the Devonian rocks of New Brunswick. This fossil, and those accompanying it, are the oldest insect-remains in the world. Fig. G. Three facets from the eye of an msect, considered by Dr. Dawson a Dragon-fly. It was found in coprolites of reptiles in the rocks containing the My- riopod, represented in Fig. 4. Copied from Dr. Dawson's figure, greatly magnified. Fig. 7. Homothetus fossilis. A Ncuropterous insect from the Devonian rocks of New Brunswick ; it was discovered by Mr. Hartt. Fig. 8. JTaplophlebium Darnesii. A curious Ncuropterous insect, of large size, probably allied to our May-flies; taken by Mr. Barnes from the coal of Cape Bre- ton. These figures, with the exception of 1, 4, and (!, are of life size, and borrowed from the new edition of Dr. Dawson's Acadian Geology. Plate 1, Fig. I I Pig.2. Fig. 3. Fig. 4. Fig. 5. Fig. 7. Fig. 6. Fig. 8. FOSSIL insec;ts GEOLOGICAL DISTRIBUTION. 79 the characters of the Neuroptera and Hemiptera. It is a large insect, spreading about two inches ; its body must have measured over an inch in length. In the Mesozoic rocks, the celebrated Solenhofen locality in Bavaria is rich in Liassic insect-remains. Dr. Ilagen (Ento- mologist's Annual, London, 1862) states that among the Solen- hofen fossils the Neuroptera and Orthoptera are most largely represented ; as out of four hundred and tifty species of insects, one hundred and fifty are Neuroptera, of which one hundred and thirt^'-six are Dragon-flies, and besides "there is a Cory- dahis, one CImjsojxi, a large Apochrysa, and a beautiful Nymj)hes. The last two genera, which do not seem very remote from Chrysopa, are now found only in the Southern Hemi- sphere, Nynrphes is peculiarly an Australian genus." The Lias of England is \evy rich in fossil insects, especially the Purbeck and Ehoetic Beds (see Brodie's AVork on Fos- sil Insects and also Westwood in the Geological Journal, etc. Vol. X.). In the Trias, or New-Red Sandstone of the Connecticut Valley, Professor Hitchcock has found numerous remains of the larva of an aquatic Coleopterous insect. The insects of the Tertiary formation more closely resemble those of the present day. The most celebrated European locality is O^ningen in Switzerland. According to Professor O. Heer, over five thousand specimens of fossil insects have been found at O^ningen, comprising 844 species, of which 518 are Coleopterous. From all Tertiary Europe there are 1,322 species, as follows: 166 Hymenoptera, 18 Lepidoptera, 166 Diptera, 660 Coleoptera, 217 Hemiptera, 39 Orthoptera, and 56 Neuroptera. "If we inquire to what insect-fauna of the present i)eriod the Tertiary fauna is most analogous, we shall be surprised Xo find that most of the species belong to genera actually found in the old and the new world. The insect-ftmna of CEningen con- tains 180 genera of this category, of which 114 belong to the Coleoptera. Of these last, two {Dineutes and Caryhorus) re- main in Europe, while all the others are now found living both in Elurope and in America. The whole number of Coleopterous genera furnished by CEningen, and known to me, amount to 80 THE CLASS OF INSECTS. 158 ; those that fire oonimon to l)oth liemispheres forming then more than two-thirds of tlie whole number, while of the actual Coleopterous launa of Europe, according to the calculation of M. Lacordaire, there is only one-third. The genera found to-day in both parts of the Avorld have then during the Tertiary- epoch played a more important part than is the case now ; hence the knowledge of the character of the fauna is rendered more difficult. AVe find at QMiingen but a very small number (five) of genera exclusively European ; seventeen are found to-day in Europe, in Asia, and in Africa, but not in America. For the most part they belong to the Mediterranean fauna (comprising eight genera) and give to the insect-fauna of Q^ningen a strong- proportion of Mediterranean forms. In this fauna I only know of one exclusively Asiatic genus ; tw^o are peculiar to Africa, and two others {Anojylites and Nrnvpactiis) are American. "There are now living, hoAvever, in Europe certain genera which, W'ithout being exclusively American, since they are found in Asia and in Africa, belong more peculiarly to America ; such are BeJostomum, Ilyiiselonotas, Diplonychus, Evagorns, Sten- ojwda, Plecia, Caryborus, and Dineutes. . . . The genera i^eculiar to our fauna of Tertiary insects amoinit to forty-four, of which twenty-one belong to the Coleoptera ; among the Orthoptera there is one, and six H^-menoptera, six Diptera, and eleven Hemiptera. They comprise 140 species." (Heer.) An ai)parently still richer locality for Tertiary insects has l)een discovered by Professor Denton west of the Rocky j\Ioun- tains, near the junction of the White and Green Rivers, C'olo- rado. According to Mr. Scudder "between sixty and seventy species of insects were brought home, representing nearly all the different suborders ; about two-thirds of the species were Flies, — some of them the perfect insect, others the maggot-like larvje, — but, in no instance, did both imago and larva of the same insect occur. The greater part of the beetles were quite small ; there were three or four kinds of Homoptera (allied to the tree-hoppers), Ants of two different genera, and a poorl}' preserved Moth. Perhaps a minute Thrips, belonging to a group Which has never been found fossil in any part of the world, is of the greatest interest." He thus sums up what is knoA>-n of American fossil insects. THE DISEASES OF INSECTS. gj "The species of fossil insects now known from North America, number eighty-one : six of tliese belong to the Devonian, nine to the Carboniferous, one to the Triassic, and sixty-five to the Tertiary epochs. The Ilymenoptera, Ilomoptera, and Diptera occur only in the Tertiaries ; the same is true of the Lepidop- tera, if we exclude the Morris specimen, and of the Coleoptera, with one Triassic excei)tion. The Orlhuptera and Myriopods are restricted to the Carboniferous, while the Xeuroptera occur both in the Devonian and Carboniferous formations." Mr. Scudder describes from the Carboniferous formation of Nova Scotia, besides Xylobius sigillarke Daws., four additional spe- cies {X. similis, fractus and Dawsoni, and Arcliiulus xyloMo- ides, n. g. and sp.), forming the family Archiulidce. The Diseases of Insects have attracted but little atten- tion. They are so far as known mostly the result of the attacks of parasitic plants and animals, though epidemics are known to break out and carry olf myriads of insects. Dr. Shimer gives an account of an epidemic among the Chinch bugs, which "was at its maximum during the moist warm weather that fol- lowed the ccVl rains of June and the first part of July, 18G5." Species of microscopic plants luxuriate in infinitesimal for- ests within the alimentary canal of some wood-devouring insects, and certain fungi attack those species which are exposed to dampness, and already enfeebled by other causes. Among the true ento2:>hyta, or parasitic plants, which do not howcAer ordi- narily occasion the death of their host, Professor Leidy describes Enterohryns elegans, E. S2m-alis, E. uUernatxis, Artliromitus cristatus, Cladophytum coviatvm, and CorT/nocIadvs radiatus, which live mostly attached to the mucous walls of the interior of the intestine of Jnltis marginatus and two other species of Jnhis, and Passahis cormitus. Eccrhia louga Leidy, lives in J'ohjdcsmns Virginiensis ; and E. moniliformis Leidy in P. grdhvJatvs. But there are parasitic fungi tliat are largely destructive to their hosts. Such are Sphaeria and Isaria. "These fun"-i groAv with great rapidity within the body of the animal they attack, not only at the expense of the nutritive fluids of the latter, but, after its death, all the interior soft tissues aijpear 6 82 THE CLASS or INSECTS. to be converted into one or more aerial receptacles of spores." (Leidy.) These fungi, so often infesting caterpillars, are hence called "caterpillar fungi." They fill the whole body, distend- ing even the legs, and throw out long filaments, sometimes longer than the larva itself, giving a grotesque ai)pearance to the insect. Leidy has found a species which is ver^' common in the Seventeen-3'ear Locust, Cicada septendechn. He found "among myriads of the imago between twelve and twenty specimens, which, though living, had the posterior third of the abdominal contents converted into a dry, powdery, oclu-eous- yellow, compact mass of sporuloid bodies." He thinks tliis Cicada is very subject to the attacks of these fungi, and that the spores enter the anal and genital passages more readily than the mouth ; thus accounting for their development in the abdomen. The most formidable disease is the '•'• Muscardine" caused by a fungus, the Botrytus Bassiana of Balsamo. It is well known that this disease has greatly reduced the silk crop in Europe. Balbiani has detected the spores of this fungus in the eggs of Bombyx mori as well as in the diftcrent parts of the body of the insect in all stages of growth. Extreme cleanliness and care against contagion must be observed in its prevention. Among plants a disease like Muscardine, due to the presence of a mimite fungus {3Iucor ludUtophorns)^ fills the stomach of some insects, including the Honey-bee, with its colorless spores, and greatly weakens those aliected. Another fungus. iSporendonema muscce, infests the common House-fly. Another Silk- worm disease called '■'■ Pehmie" carries off many silk-worms. Whether it is of pathological or vegetable origin is not yet settled. There are also a few intestinal worms known to be para- sitic in insects. The well-known "Hair-worm" {Gordius) in its young state lives within the body of various insects in- cluding the Spiders. The tadpole-like j'oung differs greatly from the parent, being short, sac-like, ending in a tail. Upon leaving the egg they work their way into the body of insects, and there live on the fatty substance of their liosts, where they undergo their metamorphosis into the adult hair-like worin. and make their waj^ to the pools of water in which they live THE DEFORMITIES OF ESTSECTS. 83 and beget their species, and lay "millions of eggs connected together in long cords." Leidy thus writes regarding tlu- habits of a species which infests grasshoppers. "The number of Gordii in each insect varies from one to five, their length from three inches to a foot ; they occupy a position in the visceral cavity, where they lie coiled among the viscera, and often extend from the end of the abdomen forward through the thorax even into the head ; their bulk and weight are fre- quently greater than all the soft i)arts, including the muscles, of their living habitation. Nevertheless, with this relatively immense mass of parasites, the insects jump about almost as freely as those not infested. "The worms are millv-white in color, and undivided at the extremities. The females are distended with ova, but I have never observed them extruded. When the bodies of Grass- hoppers, containing these entozoa, are broken and lain upon moist earth, the worms gradually creep out and pass below its surface." Goureau states that Filaria, a somewhat similar worm, in- habits Ilibeniia brumata and Vanessa jyi'orsa. (Ann. Ent. 8oc. France.) Siebold describes Gordlus svbbifnrcxs which infests the Honey-bee, especially the drones, though it is rather the work- ers, which frequent the pools Avhere the Gordii live, that wi' would expect to find thus infested. Another entozoan is 3Ier- mis albicans of Siebold, which is a very slender Avhitish worm much like Gordlus. and about five inches long. It is found in the drone of the honey-bee and in some other insects. Deformities of Insects. Numerous instances of supernume- rary legs and antennae are recorded. The antennae are some- times double, but more commonly the legs. "Of these As- muss has collected eight examples, and it is remarkable that in six of them the parts on one side are treble." Newport, from whom we have quoted, states that "the most remarkable ex- ample is that given by Lefebvre of Scarites Pi/rctchmon in which from a single coxa on the left side of the prosternum two tro- chanters originated. The anterior one, the i)roper trochanter, supported the true prothoracic leg ; Avhile the posterior one, in the form of an oblong lanceolate bod^', attached to the base of 84 THE CLASS Of insects. the first, supported two additional legs equally well formed as the true one." The wings are often partiall}' aborted and deformed ; this is especially noticeable in the wings of butterflies and moths. Mr. F. G. Sanborn has described and figured a wing of a female of JJhelhda ludnoHa Bnrm. (Fig. 69), in which among other deformities "tlie ptero- ^''o- ^^- stigma is shorter and broader than that of the opposite Aving, and is situated about one-eighth of an inch only from the nodus, only oie cubital vein occurring between them, instead of fourteen as in the opposite wing." (Proceed- ings of the Boston Society of Natural History, vol. xi, p. i52G.) Directions for Collkcting and Preserving Insects. Insects ditfer sexually in that the female generally {ii)pears to have one abdominal ring less (one ring disappearing during the i-emi-pupa state, when the ovipositor is formed), and in l)eing larger, fuller, and duller colored than the males, while the lat- ter often differ in sculpture and ornamentation. In collect- ing, Avhenever the two sexes are found united they should be l)inned ui)on the same pin, the male being placed highest. When Ave take one sex alone, Ave ma}^ feel sure that the other is somcAvhere in the vicinity ; perhaps Avhile one is flying about so as to be easily captured, the other is hidden under some leaf, or resting on the trunk of some tree near by, Avhich must be examined and every bush in the vicinity A'igorously beaten by the net. Many species rare in most places have a metropolis where they occur in great abundance. During seasons Avhen his fiivorites are especially abundant the collector should lay up a store against years of scarcity. At no time of the year need the entomologist rest from his labors. In the Avinter, under the bark of trees and in moss he can find many species, or on trees, etc., detect their eggs, Avhich he can mark for observation in the spring when the^^ hatch out. He need not relax his endeavors day or night. Mothing is night employment. Skunks and toads entomologize at night. Early in the morning, at suurise, when the dcAv is still on the leaves, insects are sluggish and easily taken Avith the hand ; COLLECTIN& AND PRESERVING INSECTS. 85 SO at dusk, when many species are found flying, and in the night, the collector will be rewarded with many rarities, man\ species flying then that hide themselves by day, wliile many caterpillars leave their retreats to come out and feed, when the lantern can be used with success in searching for them. Wollaston (Entomologist's Annual, I860) states that sandy districts, especially towards the coast, are at all times prefer- able to clayey ones, but the intermediate soils, such as the loamy soil of swamps and marshes are more productive. Near the sea, insects occur most abundantly beneath pebbles and other objects in grassy spots, or else at the roots of plants. In many places, especially in Alpine tracts, as we have found on the summit of Mt. Washington and in Labrador, one has to lie down and look carefully among the short herbage and in the moss for Coleoptera. The most advantageous places for collecting are gardens and farms, the borders of woods and the banks of streams and ponds. The deep, dense forests, and open, treeless tracts are less prolific in insect life. In winter and early spring the moss on the trunks of trees, when carefully shaken over a newspaper or white cloth, reveal many beetles and Hymenoptera. In the late summer and autumn, toadstools and various fungi and rot- ten fruits attract many insects, and in early spring when the sap is running we have taken rare insects from the stumps of freshly cut hard-wood trees. Wollaston says, "Dead animals, partially-dried bones, as well as the skins of moles and other vermin which are ordinarily hung up in fields are magnificent traps for Coleoptera ; and if any of these be placed around or- chards and inclosures near at home, and be examined every morning, various species of Nitidulce, Slip hi dee, and other insects of similar habits, are certain to be enticed and cap- tured. "Planks and chippings of wood may be likewise employed as successful agents in alluring a vast number of species which might otherwise escape our notice, and if these be laid down in grassy places, and carefully inverted every now and then with as little violence as possible, many insects will be found adhering beneath them, especially after dewy nights and in showery weather. Nor must we omit to urge the importance 86 THE CLASS OF INSECTS. of examining the under sides of stones in tlic vicinity of ants' nests, in which position, during the spring and summer months, many of tlie rarest of our native Coleoptera may be occasion- ally procured." Excrementitious matter always contains many interesting forms in various stages of growth. The trunks of fallen and decaying trees offer a rich harvest for many wood-boring larvne, especially the Longicorn beetles, and weevils can be founil in the spring, in all their stages. Nu- merous carnivorous Coleopterous and Dipterous larvje dwell within them, and other larva? which eat the dust made by the borers. The inside of pithy plants like the elder, raspberry, blackberry, and syringa, are inhabited by many of the wild f;ees, Osmia, Csratina^ and the wood-wasps, Crahro^ Stigmus, etc., the habits of which, with those of their Chalcid and Ich' neumon parasites, offer endless amusement and study. Ponds and streams shelter a vast throng of insects, and should be diligently dredged with the water-net, and stones and pebbles should be overturned for aquatic beetles, He- miptera, and Dipterous larva?. The various sorts of galls should be collected in spring and autumn and placed in vials or Ijoxes, wdiere they may be rear- ed, and the rafters of out-houses, stone-walls, etc., should be carefully searched for the nests of Mud-wasps. Collecting Apparatus. First in importance is the net. This is made by attaching a ring of brass wire to a handle made to slide on a pole six feet long. The net may be a foot in diameter, and the bag itself made of thni gauze or mosquito- netting (the liner, lighter, and more durable the better), and should be about twenty inches deep. It should be sewed to a narrow border of clotli placed around the wire. A light net like this can be rapidly turned upon the insect with one hand. The insect is captured by a dexterous twist which also throws tlie bottom over the mouth of the net. The insect should be temporarily held between the thumb and fore-finger of the hand at liberty, and then pinned through tlie thorax while in the net. The pin can be drawn through the meshes upon opening the net. The beating-net should be made much stouter, with a shal- lower cloth bag and attached to a shorter stick. It is used for beating trees, bushes, and herbage for beetles and Hemiptera COLLECTING AND rilESERVING INSECTS. 87 and various larviie. Its thorough use we would recominend in tlie low vegetation on mountains and in meadows. The water- net may be either round or of the shape indicated in Fig. 70. The ring should be made of brass, and the shallow net of grass-cloth or coarse millinet. It is used for collecting aqua- tic insects. Various sorts of forceps are indispen- Fig. 70. sable for handling insects. Small delicate narrow-bladed for- ceps with fine sharp points in use by jewellers, and made either of steel or brass, are excellent for handling minute specimens. For larger ones long curved forceps are very con- venient. For pinning insects into boxes the forceps should be stout, the blades blunt and curved at the end so that the insect can be pinned without slanting the forceps much. The ends need to be broad and finely indented by lines so as to firmly hold the pin. With a little practice the forceps soon take the place of the fingers. They will have to be made to order by a neat workman or surgical-instrument maker. Some persons use the ordinary form of pliers with curved handles, but they should be long and slender. A spring set in to separate the handles when not grasped b}' the hand is a great convenience. Various pill-boxes, vials, and bottles must always be taken, some containing alcohol or whiske}-. Many collectors use a wide-mouth bottle, containing a sponge saturated with ether, chloroform, or benzine, or bruised laurel leaves, the latter be- ing pounded with a hammer and then cut with scissors into small pieces, which give out exhalations of prussic acid strong enough to kill most small insects. Besides these the collector needs a small box lined with corn-pith, or cork, and small enough to slip into the coat- l)Ocket ; or a larger box carried by a strap. Most moths and small flies can be pinned alive without being pinched (which injures their shape and rubs off the scales and hairs), and then killed by pouring a little benzine into the bottom of the box. Killing Insects for the Cabinet. Care in killing affects very sensibly the looks of the cabinet. If hastily killed and dis- torted by being pinched, with the scales rubbed off and other- wise mangled, the value of such a specimen is diminished 88 THE CLASS OF INSECTS. either for purposes of study or the neat appearance of the col- lection. Besides the vapor of ether, chh)rofonn, and benzine, the fumes of sulpluu" readil}' kill insects. Large specimens ma}' be killed by inserting a pin dipped in a strong solution of ox- alic acid. An excellent collecting bottle is made by putting into a wide-mouth bottle two or three small pieces of cyanide of potassium, which may be covered Avith cotton, about half- filling the bottle. The cotton may be covered witli paper lightly attached to the glass and pierced with pin-holes ; this keeps the insect from being lost in the bottle. For Diptera, Loew recommends moistening the bottom of the collecting box with creosote. This is excellent for small tlies and moths, as the mouth of the bottle can be placed over the insect while at rest ; the insect flies up into the bottle and is immediatel}' suffocated. A bottle well prepared will, according to Laboulbine, last several months, even a year, and is vastly superior to the old moans of using ether or chloroform. He states, "the incon- venience of taking small insects from a net is well known, as the most valuable ones usually escape ; but by placing the end of the net, filled with insects, in a Avide-mouthed l)ottle, and putting in the cork for a few minutes, they Avill be suffocated." Pinning Insects. The pin should be inserted through the thorax of most insects. The Coleoptera, however, should be pinned through the right wing-cover ; many Ilemiptera are best pinned through the scutellum. The specimens should all lie pinned at an equal height, so that about one-fourth of the pin should project above the insect. Tlie best pins are those made in Berlin l)y Klager. They are of five sizes. No. 1 being the smallest; Nos. 1, 2, and 5 are the most convenient. For very minute insects still smaller pins are made. A ver\' good but too short pin is made by Edles- ton and Williams, Crown Court, Cheapside, London. Their Nos. 19 and 20 may be used to impale minute insects upon, and then stuck through a bit of cork, or pith, through which a No. 5 Klager pin may be thrust. Then the insect is kept out of the reach of devouring insects. Still smaller pins are made by cutting off bits of very fine silvered wire at the right length, which may be thrust by the forceps into a piece of pith, after the insects have been impaled upon them. COLLECTING AND PRESERVING INSECTS. 80 Small insects, especially beetles, may be mounted on c-irds or pieces ol" mica tln-ough which the pin may be thrust. Tiie French use small oblong bits of mica, with the posterior lialf covered with green paper on which the number may be placed, Tiie insect ma}- be gummed on the clear part, the two sexes to- gether. The under side can be seen througli the thin mica. Otliers prefer triangular pieces of card, across tlie end of which the insect may be gummed, so that nearly the whole un- der side is visible. Mr. Wollaston advocates gumming small Coleoptera upon cards. Instead of cutting the pieces of cards first, lie gums them promiscuously upon a sheet of card-board. "Having gummed thickly a space on your card-board equal to, at least, the entire specimen when expanded, itlace the beetle upon it, drag out the limbs with a pin, and, leaving it to dry, go on with the next one that presents itself. As the card has to be cut after- wards around 3'our insect (so as to suit it), there is no advan- tage in gumming it precisely straight upon, your frame, — though it is true that a certain amount of care in this respect lessens your after labor of cutting-off very materially. When ^-our frame has been filled, and you are desirous of separating the species, cut out the insect with finely pointed scissors." For mending broken insects, i.e. gumming on legs and an- tennae which have fallen off, inspissated ox-gall, softened Avith a little water, is the best gum. For gumming insects upon cards Mr. Wollaston recommends a gum "composed of three parts of tragacanth to one of Arabic, l)oth in powder ; to be mixed in water containing a grain of corrosive sublimate, without which it will not keep, until of a consistency just thick enough to run. As this gum is of an extremely ab-^orbent nature, nearly a fortnight is required before it can l)e properly made. The best plan is to keep add- ing a little water (and stirring it) every few days until it is of the proper consistency. It is advisable to dissolve the grain of corrosive sublimate in the water which is poured first upon the gum." Preservative Fluids. The best for com.mon use is alco- hol, diluted with a little \vater ; or whiskey, as alcohol of full strength is too strong for caterpillars, etc., since it shrivels them 90 THE CLASS OF INSECTS. Tip. Gl3'ccrinc is excellent for preserving the colors of cater- pillars, though the internal parts decay somewhat, and the specimen is apt to fiiU to i)ieces on being roughly handled. Laboulbene recommends for the preservation of insects in a fresh state plunging them in a preservative fluid consisting of alcohol with an excess of arsenious acid in fragments, or the common white arsenic of commerce. A i)int and a half of al- cohol will take about fourteen grains (troy) of arsenic. The living insect, put into this preparation, absorbs about jr?oo of its own Aveight. When soaked in this liquor and dried, it will be safe from the ravages of Moths, Anthrenus, or Dermedes. Tliis liquid will not change the colors of blue, green, or red beetles if dried after soaking from twelve to twenty-four hours. He- miptera and Orthoptera can be treated in the same way. A stay of a month in this arseniated alcohol mineralizes the insect, so that it appears very hard, and, after drying, becomes glazed Avith a white deposit Avhich can, however, be Avashed off" with alcohol. In this state the specimens become too hard for dissection and study, but Avill do for caljinet specimens designed for permanent exliibiti(Mi. Another preparation recommended hy LaboulbL-ne is alcohol containing a A'ariable quantity of corrosiA'c sublimate, but the latter has to be Aveighed, as the alcohol evaporates easity, the liquor becoming stronger as it gets older. The strongest solu- tion is one part of corrosive sublimate to one hundred of alco- hol ; the Aveakest and best is one-tenth of a part of corrosive sublimate to one hundred parts of alcohol. Insects need not re- main in this solution more tlian two hours before drying. Both of these preparations are very poisonous and should be handled with care. The last-named solution preserves specimens from mould, Avhicli Avill attack pinned insects during damp summers. A A'cry strong l)rine Avill preserve insects until abetter liquor can be procured. Professor A. E. Verrill recommends two sim- ple and cheap solutions for preserving, among other specimens, the larvie of insects "Avith their natural color and form remark- ably perfect." The first consists of two and a half pounds of common salt and four ounces of nitre dissolved in a gallon of water, and filtered, Spi'cimens should be prepared Cor perma- nent preservation in this solution by being l)re^■iously immersed COLLECTING AND PRESERVING INSECTS. 91 in a solution consisting of a quart of the lirst solution and two ounces of arseniate of potash and a gallon of water. (Pro- ceedings Boston Society Nat. Hist., vol. x, [). 257.) The nests, cocoons, and chrysalids of insects may be pre- served from injury from other insects by being soaked in the arseniated alcohol, or dipi)ed into benzine, or a solution of car- bolic acid or creosote. Preparinrj Insects for the Cabinet. Dried insects may be moistened by laying them for twelve or twenty-four hours in a box containing a layer of wet sand, covered with one thick- ness of soft paper. Their wings can then be easily spread. iSetting-boards for spreading the wings of insects may be made by sawing deep grooves in a thick board, and placing a strip of pith or cork at the bottom. The groo\e may be deep enough to allow a quarter of the length of the pin to project above the insect. The setting-board usually consists of thin j)araUel strips of board, leaving a groove between them wide enough to receive the body of the insect, at the bottom of whicli a strip of cork or pith should be glued. The ends of the strips should be nailed on to a stouter strip of wood, raising the surface of the setting-board an inch and a half so that the })ins can stick tlu'ough without touching. Several setting-boards can be made to form shelves in a frame covered with wire gauze, so that the specimens may be preserved from dust and destructive in- sects, while the air may at the same time have constant access to them. The surface of the board sliould incline a little to- wards the groove for the reception of the insect, as the wings often gather a little moisture, relax and fall down after the insect is dried. Moths of medium size should remain two or tiu'ee days on the setting-board, while the larger thick-bodied Sphinges and Bomhycidce require a week to dry. The wings can be arranged b}^ means of a needle stuck into a handle of wood. They should be set horizontally, and the front mar- gin of the fore-wings drawn a little forward of a line perpen- dicular to the body, so as to free the inner margin of the hind wings from the body, that tlieir form may be distinctly seen. When thus arranged, they can be confined by pieces of card l)inned to the board as indicated in figure 71, or, as we prefer, t>y square pieces of glass laid upon them. 92 THE CLASS OF INSECTS. After the insects have been thoroughly dried tliey should not be placed in the cr.binet until after having been in quarantine to see that no eggs of Uerniestes or \o »'. AN Anthrenus, etc., have been deposited on them. For preserving dried insects in the cabinet Laboulbene recommends plac- ing a rare insect (if a beetle or any Fig,-. 71. other hard insect) in water for an hour until the tissues be softened. If soiled, an insect can be cleansed under water with a fine hair-pencil, tlien submit it to a bath of arseniated alcohol, or, better, alcohol with corrosive sul)limate. If the insect becomes prune-colored, it should be washed in pure alcohol several times. This method will do for the rarest insects ; the more common ones can be softened on wet sand, and then the immersion in the arseniated alcohol suffices. After an immersion of an hour or a quarter of an hour, according to the size of the insect, the pin is not affected by the corrosive sublimate, but it is better to unpin the insect previous to immersion, and then pin it when almost dry. For cleaning insects ether or benzine is excellent, api)lied with a hair-pencil ; though care should be taken in using these substances which are very inflammaljle. After the specimens are placed in the cabinet, the^' should be farther protected from destructive insects by placing in the drawers or boxes pieces of camphor wrapped in paper perfo- rated by pin-holes, or bottles containing sponges saturated with benzine. The collection should be carefully examined ever}' month ; the presence of insects can be detected by the dust beneath them. AVhere a collection is much infested witli destructive insects, benzine should be poured into the bottom of the box or drawer, when the fumes and contact of the ben- zine with their bodies will kill them. The specimens them- selves should not be soaked in the benzine if possible, as it renders them brittle. Insect-cabinet. For permanent exhibition, a cabinet of shal- low drawers, protected by doors, is most useful. A drawer may be eighteen by twenty inches square, and two inches deei) in the clear, and provided with a tight glass cover. For constant COLLECTING AND PRESERVING INSECTS. 93 use, boxes made of thin, well-sefisoned wood, with tight-fitting covers, are indispensable. For Coleoptera, Dr. Leconte recom- mends that tliey be twelve by nine inches (inside measnrement). For the larger Lepidoptera a little larger box is preferable. Others prefer boxes made in the form of books, whicli may be put away like books on the shelves of the cabinet, though the cover of the box is apt to be in the way. The boxes and drawers should be lined with cork cut into thin slips for soles ; such slips come from the cork-cutter about twelve by four inches square, and an eighth of an inch thick. A less expensive substitute is paper stretched upon a frame. Mr. E. S. Morse has given in the American Naturalist (vol. I, ]). 150) a plan which is very neat and useful for lining boxes in a large museum, and which are placed in horizontal show-cases (Fig. 72). "A box is made of the re- quired depth, and a light frame is fitted to its in- terior. Upon the upper and under surfaces of this frame, a sheet of white paper (drawing or log- paper answers the pur- pose) is securely glued. Fig. 72. The paper, having been previously dampened, in drying con- tracts and tightens like a drum-head. The frame is then secured about one-fourth of an inch from the bottom of the box, and the pin is forced down through the thicknesses of l)apcr, and if the bottom of the box be of soft pine, the point of the pin may bs slightly forced into it. It is thus firmly held at two or three different points, and all lateral movements are prevented. Other advantages are secured by this arrangement besides firmness; when the box needs cleaning or fumigation, the entire collection may be removed by taking out the frame, or camphor, tobacco, or other material can be placed on the bottom of the box, and concealed from sight. The annexed figure represents a transverse section of a portion of the side and bottom of the box with the frame. A, A, box ; B, frame ; 94 THE CLASS OF INSECTS. P, P, upper and under sheets of paper ; C, space between lower sheet of paper and bottom of box." Other substitutes are the pith of various phxuts, especially <;i corn ; and palm wood, and "inodorous felt" is used, being cut to fit the bottom of the box. Leconte recommends that "for the purpose of distinguish- ing specimens from dilferent regions, little disks of variously colored paper be used ; they are easily made by a small punch, and should bs kept in wooden pill-boxes ready for use ; at the same time a key to the colors, showing the regions em- braced by each, should be made on the fly-leaf of the catalogut' of the collection." He also strongly recommends that the "specimens should all be pinned at the same height, since the ease of recognizing species allied in characters is greatly in- creased by having them on the same level." He also states that "it is better, even when numbers with reference to a catalogue are employed, that the name of each species should be written on a label attached to the first speci- men. Thus the eye is familiarized with the association of the species and its name, memory is aided, and greater power given of identifying species when the cabinet is not at hand." For indicating the sexes the astronomical sign $ (Mars) is used for the male, and 9 (Venus) for the female, aiid 9 for the worker. Transportation of Insects. While travelling, all hard-bodied insects, comprising many Hymenoi)tera, the Coleoptera, He- miptera, and many Neuroptera should be thrown, with their larva?, etc., into Ijottles and vials filled with strong alcohol. When the bottle is filled new liquor should be poui-ed in, an GENERAL WORKS. The Avorks of Sioammerdam, Malphighi, Leeuwenhoek, Lyonnet, Serves, Meckel, linmdohr, Suckoto, Merian, and Herhst. Reaumur, Rene Ant. cle. Memoires pour servir a P Histoire cles Insectes. Paris, 1734 -1742, 7 vols. 4to. Roesel, Aucj. Joh. Dermonatlich heransgegeben Insekten-Belustigung. Niirnberg, 174G-17(n, 4 vols. 4to, illustraterl. Geer, Carl de. Memoires pour servir a 1' Histoire des Insectes, 1752-1778, 7 vols. 4to. Linnceus, Carolus. Systenia ?riii!-h Museum. London, 184S-(i7. Amyot, C, and ServUle, A. llemipteres. 8vo, Paris, Horet, 184;{. Ratzeburg.J.T.C. Die Forstinsekten. 4to, 3vols. Berlin, 1837-44. Van der Hceven, J. Handbook of Zoology, English tran.-lalion. 2 vols. 8vo, 1850. Gerstaecker, A. Handbuch der Zocilogie (in connection with V. Cams), 2 vols. 8vo. (vol. 2, Arthropoda). Leipzig, 1863. Be .S'e/?/.s' Loiif/champs, E. Revue des Odonatc-s on Libellules d'Enrope avee la col- laboration de H. Hagen. Paris, 1850, 8vo. (Memoir. Soc. R. Science de Liege, vol. vi.) (Two species. Lib. Hudso7iica, p. 53, and Agrion Doubledayi, p. 209, are described in this work.) Hagen, H. Revue des Odonates; Monographie des Calopterygines; Monogi'aphie des Gomphines (cf. Sclys Longchanijjs). Agassiz, L. Lake .Superior, its Physical Character, its Vegetation, and its Animals, Boston, 18.50. With Catalogue of Coleoptera, by Dr. J. L. Leconte, and of the Lei)idoiitera, by Dr. T. W. Harris. Lacazc-Duthiers, H. Recherches sur V aiTnure genitale femelle des Insectes. Plates. 8vo. Paris, 1853. Melsheimer, F. E. Catalogue of the described Coleoptera of the United States. Smithsonian In.«titution. 8vo, 18.53. Dallas, ir. S. Catalogue of Hemipterous Insects in the British Museum. 1, 3. Illustrated. Loudon, 1852. Fitch. Asa. The noxious, beneficial, and other Insects of the State of New York, Reports 1-8, 185(j-:j(i. Sjniili, Frederic. Catalogue of Hymenoptera in the British Museum. Parts i-vl. Plates. London, 1857-.58. Fallen, C. F., Stal, C, and Fieber. Various papers on Hemiptera in Scandinavian and German periodicals. Hiibner, J. Saminlung Exotischer Schmetterlinge. 5 vols. 4to. Plates. 1800. Guenee, A. Species general des Lepidopteres. (Noctuidre, Phalsenidas and Pyra- lida') Suite a Buflbn. Paris, 8vo, 1852-57. Stainton, H. T. The Natural History of the Tineina. 8vo, with many plates. Lon don, vols. 1-8, 185.")-nt, 8vo. Lacordaire, J. T. Genera des Coleopteres. 8vo, tomes 1-7. Paris, Roret, 18.54. Jloisduval, J. A. Histoire generale et Iconographie des Lepidopteres et des Che- nilles de 1' Amerique septentiionale. 8vo. Paris, Rorct, 1829-42. Species generale des Lepidopteres. 8vo. Roret, Pans, 185G. . Kssai sur 1' Eutoniologie horticole. 8vo. Paris, 1SU7. Practical Entomologist. Entomological Society of Philadelphia. Vols. 1, 2, 4to, 18(i.5-()7. Harris, T. W. A Treatise on some of the Insects of New England, which are injurious to Vegetation. Third edition, illustrated. Boston, 1862. Leconte, J. L. Classification of the Coleoptera of North America. Part I, 1861 Smithsonian Institution. . List of Coleoptera of North America. 8vo, 186.3-6. Smithsonian Institu- tion. . New Species of North American Coleoptera. 8vo. Part 1, 1863-6. Smith sonian Institution. Coleoptera of Kansas and Eastern New Mexico. 4to. 3 plates. 18.5!), Smithsonian Institution Hagen, H. Synopsis of the Neuroptera of North America. 8vo. 1861. Smitlv sonian Institution Morris, J. G. Catalogue of the described Lepidoptera of North America. 8vo, 1860. Smithsonian Institution ENTOMOLOGICAL WORKS. 101 Osten Snclcen, 11. Cntalogue of the (lescribed Diiitora of North America. ISflS. Smithsonian institution. Loeiu, II., and Osten Sacken, It. Monograph of the Diptera of North America. Parts 1,2, Svo, 18(i2-(>4. Smithsonian Institution. Trimble, I. P. A Treatise on the Insect Enemies of Fruit and Fruit Trees. The Curculio and Apple moth. 4to. Plates. New York, 18(J5. MORPHOLOGY. Savigny, J. C. Memoires sur les Animaux sans Vortebrcs. 1 Partic. Description et Classification des Animaux invertebres et articules, I. Fascicule. Tlieorie des Organes de la Bouche des Crustaces et des Insectes. Paris, 1810. Audouin, J. V. liecherches anatomi(iues sur le Thorax des animaux articulos et celui des Insectes hexapodes en particulier. (Aunales d. Scienc. natur. 1, 1824, p. 97 and 41C.) Eschscholts, J. F. Beschreibung des inneren Skeletes einiger Insekten aus ver- schiedeneu Ordnungen. Dorpat, 1820, Svo, p. 24-49, 2 Taf. Baer, K. E. V. Ueber das iiussere uud innere Skelet (Meckel's Archiv. f. Anatom. u. Physiol. 1S2G, p. 327-374). f:richsoii, IF. F. Ueber zocilogische Charaktere der Insekten, Arachniden mid Crustaceen. (Entomographien, S. 1-28.) Berlin, 1840, Svo. Bridle, A. Kecherches sur les Transformations des Appendices dans les Arti- culcis (Annales des Sciences natiirelles,3. ser. II, 1844, p. 271-374). Lexickart, R. Ueber die Morphologic und die Verwaudtschaftsverhaltnisse der Wirbelloseu Thiere. Braunschweig, 184S, Svo. ANATOMY AND PHYSIOLOGY. Straus- Diirclcheim, IT. Considerations gene-rales sur I'Anatomie comparee des Animaux articiiles, anxquelles on a joint 1' Anatomic descriptive du Melolontha vulgaris. Paris, 1828, 4to. 10 pi. Diifour, L. fsumerous anatomical papers in the Annales des Sciences naturelles, Paris. SieboM, C. Th.i\ Lehi-biich der Vergleichenden Anatomic der wirbellosen Thiere. Berlin, 184S, Svo. Translated by W. I. Burnett. Boston, IS.'il, Svo. Gegeiibcnir, C. Grundzlige der vergleichenden Anatomic. Leipzig, IS.W, Svo. Geoffroij St. ITilaire, Etienne. Considerations philosophiques sur la determination du Systeme solide et du Systeme nerveux des Animaux articules. (Annal. d. scienc. natur. II, 1824, p. 29.5 ff., Ill, p. 199 u. p. 453 ff.) Neioport, G. On the Structure, Relations, and Development of the nervous and circulatory Systems, and on the existence of a complete Circulation of the Blood in Vessels, in Myriapoda and Macrourous Arachnida. (Philosoph. Transact- 1S43, p. 243-302.) . On the Structure and Development of the Blood, I. ser. The Development of the Blood Corpuscle in Insects and other Invertebrata, and its Comparison with that of Man and the Vertebrata. (Annals of Nat. Hist. XV, 184.'), p. 2S1-2S4.) . On the Nervous System of the Sphinx ligustri Lin. and on the Changes which it undergoes during a Part of the Metamorphoses of the Insect. (Philo- soph. Transact. 1S32, p. .383-398, and 18.34, ,3S'.)-423.) . On the Temperature of Insects and its Connexion with Functions of Res- piration and Circulation in this class of Invertel)rated Animals. (Philosoph. Transact. 1837, p. 2.59-3.38.) Blanchard, E. Recherchcs anatomiques et zoologiques sur le Systeme nerveux des Animaux sans vertebres. Du systeme nerveux des Insectes. (Annal. d. scienc. natur. 3. ser. V, 1846, p. 273-379.) 102 THE CLASS or INSECTS. lilanchard, E. V>\\ Syst^me nerveux chcz les Invert(''bres dans ses rapports avec la Classification de ces Aninianx. Paris, 1849, 8vo. Milne- FAlicariU, H. Legons sur la Physiologic ct 1' Anatomic comparee de I'Homme et des Auiinaiix. Paris, Masson 1857-04, 8vo. EMBRYOLOGY. JiathJce, IT. Untersnchnngen iibcr die Bildung nnd E;ntwickelung des Flusskreb- ses, Leipzig, Voss. 1820, Fol. initS Tal". . Znr Morphologic, Reisebemerknngcn aiis Tanrien. Riga, 1837, 4to, niit 5 Taf. Ilerold, J. ^r. Excrcitationcs de animalium vertcljris carentiiim in ovo formatione I. De generatione Arancanun in ovo. — Unter?nchnngen liber die Bildnngsge- schichtc der Wirbellosen Tliiere im Ei. 1. Th. V'on dcr Erzeuguug der Spinnen im Ei. Marburg, Kriegcr, 1821, fol. niit 4 Taf. . Disquisitiones de animalium vertcbris carentium in ovo formatione. Do generatione Inseutorum in ovo. Fasc. I, II, Frankfurt a Main, 183.')-.']8, fol. KuUiker, A. Observationes de prima Insectornm genesi, adjecta aiticulatornm evolutionis cum vertebratorum comparatione. Dissert, inaiig. Turici, Meyer et Zeller, 1842, 4to, c. tab. 3. Zaddach, G. Uutsrsuchung iibcr die Entwickelung iind den Ban der Gliederthici'c. Heft 1. Die Entwickelung des Phryganiden-Eies. Berlin, Rcimcr. 1854, 4to, c. tab. 5. Leuckart, R. Die Fortpflanzung iind Entwickelung der Pupiparen nach Bcobach- tnngen an Mclopliagus ovinus. (Abhandl. d. naturf. Gesellsch. zu Halle IV, 1858i S. 145-22(J.) Huxley, T. On the agamic Reproduction and Morphology of Aphis (Transact. Linnean Soc. of London, XXII, p. lf)3-2.3(:.) Lubbock, J. On tlic Ova and Pseudova of Insects (Philosophical Transactions of the Royal Soc. 18.5!), p. 341-369. Claparede, E. Recherches sur revolution des Avaignees. 4to. Utrecht, 1862. Weismnnn, A. Ueber die Entstelniug des voUendeten Insekts in Larveund Puppe. Ein Beitrag zur Metamorphose der Insektsn, Frankl'urt a Main, 1863, 4to. . Die Entwickelung der Dipteren im Ei, nach IJeobachtungcn an Chirono- mus, Musca vomitoria und Pulex canis (Zeitschrift fiir Wissenschaltliche Zo- ologie XIII, p. 107-204.) . . Die nachembryonale Entwickelung der Musciden nach Beobachtungen an Musca vomitoria und Sarcophaga carnaria. (The same, XIV, p. 187-336.) FOSSIL INSECTS. Giebel, C. Fauna der Vorwelt mit steter Beriicksichtigung der lebenden Thiere. 2. Bd. Gliederthiero. 1. Abtheilung. Die Insekten und .Spinnen dcr Vorwelt mit steter Beriicksichtiginig der lebenden Insekten und Spinnen. Leipzig, 1856, 8vo. Berendt, C. G. Die im Bernstein beflndlichen organischen Restc der Vorwelt, ge- sammelt und in Verl)inrlung mit Mehreren herausgegeben. 1. Band. 2, Abth. Die im Bernstein befindliclien Crustaceen,Myriai)odon, Arachniden undapteren der Vorwelt, bearbeitet von C. L. Koch und C. G. Berevdt. — 2. Band. Die im Bernstein beflndlichen Ilcmipteren, Orthopteron, und Neuropteren der Vorwelt, bearbeitet von E. F. Gerinnr, F. J. Pictet, und H. Hmjen. Berlin, 1854-56, fol. Jleer, O. Die Insecten-faunader Tertiaergebildc von CEningen und Radoboj. Leip- zig, 1840, 4to, 3 vols. Scudder, S. H. An inquiry into the Zoological Relations of the first discovered Traces of fossil Nenropterous Insects in North America. From the Memoirs of the Boston Society of Natural History, Vol. I, 1867, with a plate. ENTOMOLOGICAL JOURNAL. 103 PERIODICAL WORKS (now in course of publication). Edimrds, W. H. Butterflies of North America. Colored plates. CoinmenccdlSCS. Anntiles de la SocietL' entoiiiologique de France, Paris. Commenced 18.52. Transactions ol' the Eulomological Society ol" London. Commenced 1834. L' Insectologie Af/ricole, Monthly Journal, Paris. Conmienced 18U7. Zeitung. Entoniologische Verein, Stettin. Commenced 1810. lAnncea entomnlogica. Entomologische Verein, Berlin. Commenced 1846. Zeitschrift. Entoniologische Verein, Berlin. Commenced 18.")7. Annales de la Societe entomologiqne Beige, Brussels. Commenced 18.57. /VoceerfiHjrs of the Academy of Natural Sciences, Philadcli)hia. Commenced 1819. Journal of the Academy of Natural Sciences, Philadelphia. Commenced 1817. Transactions of the American Philosophical Society. New Series. Commenced 1818. Proceedings of the Boston Society of Natural History. Commenced 1834. Journal of the Boston Society of Natural History. Commenced 18.34. Annals of the Lyceum of Natural History of New Yorl^. Commenced 18'24. Proceedings and Transactions of the American Entomological Society, Philadel- phia. Commenced 1861. Proceedings and Communications of the Essex Institute, Salem. Commenced 1818. American Naturalist, Philadelphia. Commenced March, 1867. Entomological Journal. Every collector should keep a daily journal of his captures and observations, noting down eveiy fact and hint that falls under his notice. In this book, commenced as soon as the season opens in early spring, can be placed on record the earliest appearance, the time of great- est abundance, and the disappearance of every insect in any of its stages. Also the descriptions of larv?e, with sketches, and observations upon their habits ; though drawings had better be kept upon separate pieces of paper for easier reference. The insects, when captured and unnamed should be numbered to agree with corresponding numbers in the note-book. At the close of the season one will be surprised to see how much material of this kind has accumulated. He can then make a calendar of appearances of perfect insects and larvae, so as to have the work of the next season portioned out to him ; he will thus know Avhen and where to look for any particular insect or caterpillar. The Number of Species of Insects. Oswald Heer estimates that the Insects comprise four-fifths of the whole animal king- dom. While there are about 55,000 species of animals known, excluding the Insects, the number of this last single class amounts to upwards of 190,000 known species, according to 104 THE CLASS OF INSECTS. Gei'staecker's estimate. He reckons that there are at least 25,000 species of Hymenoptera, from 22,000 to 24,000 Lepidop- tera, about 24,000 Diptera, and 90,000 Coleoptera ; the number of the other suborders cannot be easily estimated. Besides these there are about 4,600 Arachnida, and 800 Myriopods. GuoupiNCr OF Insects into Orders and Suborders. Be- fore beginning an account of the Six-footed Insects, we present the following tabular view of the Classhlcation of In- sects. The idea that the Myriopods, Spiders, and Six-footed Insects formed orders and not classes was llrst proposed by R. Leuckart in 1848, and afterwards supported by Agassiz and Dana. The arrangements proposed by these and other authors are put in tabular form on page 106. The Class of Insects. Sub-dass I. Segments grouped into thi'ee distinct re- "1 gions; eyes compound and simple; two piiirs of j IIexapoda wings:* tliree pairs of tlioracic legs; one pair of ^(Six-footed In- jointed abdominal appendages. A more or less | sects). complete metamorphosis, . . . . .J Sub- class ILSc'^mcnta gfouped into two regions, a^ false cephalothorax fund an abdomen; noantennne; I A^\c^^^nA eyes simple; wingless; four pairs of thoracic legs ; y (^ryiA^ra) three pairs of jointed abdominal appendages (spin- I ^ ^ ^' ne'rets) often present. No metamorphosis, . . J S;ib-rlnss TTLBody cylindrical, worm-like. Segments ^ not grouped into regions. Head free; eyes sim- ple ; antennae present ; wingless ; uuraerous ab- dominal legs present; yelk-sac present for a short period after hatching. No metamorphosis. Myriopoda (Centipedes). The Orders of Six-footed Insects J (Hexapoda). Mctahola. The body usually cylindrical; prothorax ^ small; mouth-parts more generally haustellate | Hymenoptera (formed for sucking) ; metamorphosis complete ; )■ Lepidoptera. pupa inactive; larva usually cyliudrical, very | Diptera. unlike the adult, J ^etrrometabola. The body usually flattened; pro- ^ Coleoptera. thorax large and squarish; mouth-parts usually j Hemiptera. adapted for biting; metamorphosis in a large }« Orthoptera. number incomplete; pupa often inactive; larva j Neuroptera. flutteued, often resembling the adult, . . J Thysanura. * The number of wingless forms is comparatively few. The Diptera have but one pair. fTlie so-called " cephalothorax" of Spiders is not like that region in the Crabs, the head being much freer from the thorax. X Leuckart's classification is an advance on others in his considering the Hexa- poda, Arachnida, and Myriapoda as orders instead of classes, but he says nothing GROUPING OF INSECTS. lOfj The following diagrani shows, in a nulc way, the relative rank and affinities of the eight orders, and of the two series of Six-footed Insects. Neuroptera. Thysanura. Through Lejnsma, and Podura which are wingless Thysa- nurous insects, the lower series is connected with the Myriopods, the minute degraded Fauropus and Scolopendrella perha})s forming the connecting links ; and through the wingless flies, Brcmla^ Chionea, and Nycteribia, the Diptera, belonging to the higher series, assume the form of the Spiders, the head being small, and sunken into the thorax, while the legs are long and slender. The first and highest series culminates in A2ns, the Honey-bee ; and the second, or lower, in Cicindela, the Tiger-beetle. regarding the rank and valne of the minor groups. Professor Agassiz extended Leuckart's views in considering the seven grand divisions of the order of Ilexapods as suborders. In 1803 (How to Observe and Collect Insects, jNIaine Scientific Sur- vey, and Synthetic Types of Insects, Boston Journal of Natural History), we proposed a new classification of these divisions, by which they are thrown into two main groups headed by the Hymeuoptera and Coleoptera respectively. These two groups, as represented in tlie diagram, are nearly equivalent in value, ami stand in a somewhat parallel relation. Tliere is nothing like a linear series in the aiiimal kingdom, but it is like a tree. Tlie hiiilier series of orders form more of i— O. i) O i< 0; o ^ i- _;KP-t;^:)3HZrioSOcc Arachnida. Suborders 1-3. Araueoids, Scorpiouoids, Acaroids. Myriopoda. Suborders 1-2. Cliilopods, Diplopods. a" &4 S ;--. O — 3 '^ •- ^ 03 S»-J3oSO'k^ CO 1 • T-H "S S a .2 g S 5 3 o S 5~ X: ■" zj ^ ■; ji o o < CO "7 .. « "s o — ^ '^< 1- o ^ 1 c« ^QSKOOZ ^ 1 E o g S s 1 2 -^ r^ ?2 S 2 ^ -^ o a-rt.S" 5 ^ O c t^ 3 3 >. iT"' 3 — ' 3 ■S .2 o 8 ■^ O t; ^^ 5 ^ O rt irt^ o o ? 3 o « O ir^Hi 3 3 do S O ^ O S < * CD ;2 to 2 U 1 i o 2 ci^ 11 '-'^ •-- '^ s 'S 1^ - d~ ^"^ S s 1 I- ^ Illllii 1st O o «J o ij >i-=^ a 2 2^? s IS 25 'i'i C tH f3 c3 -« i5 e O « £:.« ■" y S .2 o ^^ — ^ O "3 s o . s ^-^ so 3 o 1 o HYMENOPTERA. 107 HYMENOPTERA. The Bees, Wasps, Saw-flies, Ants, and other members of this suborder differ from all other insects in liaving, in the liigher and more typical forms, the basal joint of the abdomen thrown for- ward upon and intimatelj^ united with the thorax. The head is large, with large compound eyes, and three ocelli. The mouth-parts are well developed both for biting, and feeding on the sweets of plants, the ligula especially, used in lapping nectar, being greatly developed. The other regions of the body are more distinct than in other insects ; the wings are small but powerful, Avith comparatively few and somewhat irregular veins, adapted for powerful and long-sustained flights ; and the genital appendages retracted, except in the Ichneu- mon parasites and Saw-flies, within the body, are in the female modified into a sting. The transformations of this suborder are the most complete of all insects ; the larvjxj in their general form are more unlike the adult insects than in any other suborder, while the pupae, on the other hand, most clearly approximate to the imago. The larva? are short, cylindrical, footless (excepting the young of the Saw-flies, the lowest family, which are provided with abdominal legs like Lepidopterous larva?), worm-like grubs, which are helpless, and have to be fed by the i)revision of the parent. The pupa has the limbs free, and is generally contained in a thin silken cocoon ; that of the Saw-flies, however, being thick. The Hymenoptera exhibit, according to Professor Dana, the normal size of the insect-type. "This arclietypic size is be- NOTE to page lOG.— Ray divided the Ilexapods into Coleoptera and Aneloptera, tlie latter division enibvacing all the other suborders except the Coleoptera. His Ametnmorphota //exo;;orfrt contained the wingless hexapoda; while the Ametamnr- phota polypoda comprise the iMyrlO))ods, and the A. octopoda the Arachnids. Lin- nfcus* Aptera (with numerous feet) are equivalent to the Myriopods,and his Aptvra (with 8-14 feet) to the Arachnids. In Fabricius' system the Eteutheratd are equiva- lent to the Coleoptera ; the f'^;o»«<« to the Orthoptera; the Si/nistata to the 'Scuvoii- tera; the Piezata to the Hymenoptera; the Odonata to theLibeliuIidw; the Gtos.iaia to the Lepidoptera; the Ilhyngota to the Hemiptera; the Antliata to the Dijitera. The ^fitosata are the Myriopods, and the Unogatn, the Arachnids. In Latreille's system the Suctoria, or Fleas, are now referred to the Diptera; the Parasita or Lice, to the Hemiptera, and the Thysanura to the Neuroptera. 108 HYMENOPTERA. tween eight and twelve lines (or twelfths of an inch) in length, and two and a half and three lines in breadtli." This size is probably a smaller average than in any other suborder ; thus the Hymenoptera while being the most cephalized, consequentl}'^ comprise the most compactly moulded insectean forms. Besides these structural characters, as animals, endowed with instincts and a kind of reason differing, perhaps, only in degree from that of man, these insects outrank all other Articu- lates. In the unusual diffierentiation of the individual into males and females, and, generally sterile workers, with a farther dimor- phism of these three sexual forms, such as Iluber has noticed in the Humble-bee, and a consequent subdivision of labor among them ; in dwelling in large colonies, thus involving new and intricate relations with other insects (such as Aphides, ant-hill-inhabiting beetles, and the peculiar bee-parasites) ; their wonderful instincts, their living principally on the sweets and pollen of flowers, and not being essentially carnivorous (/. e. seizing their prey like the Tigei'-beetle) in their hr.bits, as are a large proportion of the other suborders, with the exception of Lepidoptera ; and in their relation to man as a domestic an- imal, subservient to his wants, — the Bees, and Hymenoptera in general, possess a combination of characters which are not found existing in any other suborder of insects, and which rank them first and highest in the insect series. The body-wall of the Hymenoptera is unusually dense and hard, smooth and highly polished, and either naked, or covered Avith hair as in a large proportion of the bees. The head is large, not much smaller than the thorax, and its front is verti- cal. The antenUcTe are short, filiform, often geniculate, very rarely pectinated. The mandibles are large, stout, toothed, and the niaxilhie are well developed into their tlu'ee subdivisions, the palpi being usually six-jointed ; the labial palpi are usually four-jointed, and the prolongation of the under lip, or ligula, is highly developed, being furnished with a secondary pair of palpi, the paraglossia, while in tlie pollen-gathering species the ligula is of great length, and thus answers mucli the same purpose as the spiral tongue (maxilte) of the Lepidoptera. Reaumur states that the Bee does not suck up the liquid sweets, but laps them up with its long slender hairy tongue. HYMENOPTERA. 109 "Even in the drop of honey the bee bends the end of its tongue about, and lengthens and sliortens it successively, and, indeed, withdraws it from moment to moment." The liquid passes along the upper surface of the pilose tongue, which is withdrawn between its sheaths, the palpi and maxilljB, and thus "conveys and deposits the liquid with which it is charged within a sort of channel, formed by the upper surface of the tongue and the sheaths which fold over it, by which the liquid is conveyed to the mouth." (.Shuckard.) The thorax forms a rounded compact oval mass, with the prothorax and metathorax very small, the mesothorax being large, and also the i)ropodeum, to which the pedicel of the ab- domen is attached. The pleurites are large and bulging, while the sternum is minute. Tlie coxse and trochantines are large, and quite free from the thorax ; and the trochanters are small, while the rather slender legs are subject to great ■ modifications, as they are devoted to so many different uses by these insects ; thus, in the Sand-wasps they are strongly )n-istled for the purpose of digging, and in the Bees, the basal joint of the tarsi is much enlarged for carrying pollen. "The manner in which the bee conveys either the pollen, or other material it purposes carrying home, to the posterior legs, or venter, which is to bear it, is very curious. Tlie rapidity of the motion of its legs is then veiy great ; so great, indeed, as to make it very difficult to follow them ; but it seems first to collect its material gradually with its mandibles, from which the anterior tarsi gather it, and that on each side passes successively the grains of which it consists to the inter- mediate legs, by multiplicated scrapings and twistings of the limbs ; tliis, then, passes it on by similar manoeuvres, and de- posits it, according to the nature of the bee, upon the pos- terior tibiae and tarsi, or upon the under side of the abdomen. The evidence of this process is speedily manifested by the pos- terior legs gradually exhibiting an increasing pellet of pollen. Thus, for this purpose, all the legs of the bees are more or less covered with hair. It is the mandibles which are chiefly used in their boring or excavating operations, applying their hands, or anterior tarsi, only to clear their way ; but by the construc- tive, or artisan bees, they are used both in their building and 110 HYMENOPTER A . mining operations, and are worked like trowels to collect moist clay, and to apply it to the masonry of their habitations." (Shuckard.) The four wings are present, except in rare instances. They are small ; the hinder pair long, narrow, ovate, lanceolate. The costal edge of the fore-wing (Fig. 29), is generally straight, becoming a little curved towards the apex, which is obtusely subrectangular ; the outer edge is bent at right angles, while the inner edge of the wing is long and straight. The veins are often difficult to trace, as in the outer half of the wing they break up into a system of net-veins, which are few in number, yet the continuations of the subcostal, median, and submedian A^eins can be distinguished after careful study. In some low Ichneumonidce, the Proctotrupidce^ and Chalciclidce, the veins show a tendency to become obsolete, only the simple subcostal vein remaining ; and in Pteratomiis^ the veins are entirely obliterated, and the linear feather-like wings are in one pair fissured, reminding us of the Plume- moths, PteropJiorus. The abdomen is composed in the larva state of ten segments, but in the adult stinging Hymenoptera, of six complete seg- ments in the females, and seven in the males ; while in the lower families the number varies, having in the Tenthredi- nidce, eight tergites on the upper side and six sternites on the lower side. The remaining segments are, during the transfor- mations of the insect, aborted and withdrawn within the body. The ovipositor and corresponding parts in the male have been described on pp. 14-18. The nervous system consists in the larv?e of eleven ganglia, in the adult five or six of these remain as abdominal ganglia, while the remainder, excluding the cephalic ganglia, are placed in two groups in the thorax. The cerebral ganglia are well developed, evincing the high intellectual qualities necessary in l)residing over organs with such different uses as the simple and compound eyes, the antennje, and lingua and palpi, and mandibles, especially in those sociable species which build complete nests. The digestive system, in those bees which sip up their food, consists, besides the external mouth-parts, of a "long oesoph- I. HYMENOPTERA. HI agns which dilates into a, thin-walled sucking stomach," which in the Apiariw and Vesjiiclce may be simply a lateral fold, or, as in many Crabronidce, "attached solely by a short and narroAV peduncle." In Formica, Cyrdps, Leucospis, and Xyj)hkl- ria there is a globular uncurved callous gizzard, which is en- veloped by the base of the stomach, according to Siebold, who also states that "those Hymenoptera which are engaged during a long and active life in labors for the raising and support of their young, have a pretty long and flexuous stomach and in- testine, and the first has, usuall}^, many constrictions;" while the Gy nip idee, Ichneumonidoe, and Teuthredinidce , which take no care of their young, have only a short small stomach and intestine. The salivary glands consist of two rather short ramified tufts, often contained entirely in the head. The tracheae consist, as in other insects, of two main branches, from which numerous transverse anastomosing branches are given off, with numerous vesicular dilatations. Two such vesi- cles of immense volume are situated at the base of the abdo- men, which according to Hunter and Newport "serve chiefly to enable the insect to alter its specific gravity at pleasure dur- ing flight, and thus diminish the muscular exertion required during these movements." The urinary vessels are very numerous in the Hymenoptera ; they are usually short and surround the p3'lorus in numbers of from twenty to one hundred and fifty. The two poison glands (Fig. 54, h,g) are composed of long ramose tubes, resembling the salivary glands in their minute structure. The poison is poured from these into a pyriform sac lodged near the base of the sting, which is provided with a peculiar muscular apparatus for its sudden extension and with- drawal. The poison, in the Ants, Bees, and Wasps, consists, according to Will, of "formic acid, and a whitish, fatty, sharp residuum, the former being the poisonous substance." (Bur- nett.) The wax-secreting apparatus consists of special dermal glands, as Milne-Edwards supposed. Claus has shown (see Gegenbaur's Verg. Anatomic) that these minute glands are mostly unicellular, the external opening being through a fine chitinous tube on the outer surface of the integument. In the 1 1 2 HYMENOPTERA. wax-producing insects these glands are developed in great numbers over certain portions of tbe body. In the Aphides, whose bodies are covered with a powder consisting of fine waxy threads, these glands are collected in groups. Modifications of them appear in the Coccidae. In the wax-producing Hymen- optera the apparatus is somewhat complicated. The bees secrete wax in thin, transparent, membranous plates on the under side of the abdominal segments. Polygonal areas arc formed by the openings of an extraordinarily large number of fine pore-canals, in which, surrounded by very numerous tra- cheal branches, the cylindrical gland-cells are densely piled upon each other. These form the wax organs, over which a fatty layer spreads. In those bees which do not produce wax, the glands of tlie wax organs are slightly developed. Wax organs also occur in the Humble bees. The honey is elaborated by an unknown chemical process, from the food contained in the proventriculus, or crop, and which is regurgitated into the honey-cells. The ovaries consist of many-chambered, four, six, or a hun- dred, short tubes. "The reccqytac^da seininis is nearly always simple, round or ovoid, and necked, and is prolonged into a usually short seminal duct." The glanduJa apj^eiidicuktris con- sists of a bifurcate tube which opens into the ductus semincdis, and only rarely into the capsula semincdis itself. In the Tenthredinidce , "this apparatus is formed on a different type ; the seminal vesicle is a simple diverticulum of the vagina, and more or less distinct from it, besides it is defi- cient in the accessory gland. The copulatory pouch is absent in all the Hymenoptera, as are also the sebaceous glands with those females which have a sting and a poison gland," while in other insects the sebaceous glands are present, and it would be nat- urally inferred, therefore, that the two are homologous, but modified for diverse functions. The two testes of the male are "composed of long follicles, fasciculate and surrounded, together with a portion of the torose deferent canal, by a common envelope ; but more com- monly the two testes are contained in a capsule situated on the median line of the bod3^" (Siebold.) The eggs are usually long, cylindrical, and slightly curved in HYMENOPTERA. II3 the Bees ; in the Wasps they are more globular, and affixed by their smaller somewhat pedicelled end to the side, near the bot- tom of the cell in which they are laid. The eggs of the lower families tend to assume a spherical form. The eggs of dif- erent species of Bombus present no appreciable diffei-cnces. The larvsie of the Bees and Wasps, especially the social species, which live surrounded by their food, are of a very persistent form, the various genera differing but slightly, while the species can scarcely be separated. Such we have found to be the case in the Bees and Wasps ( Ves2-)!dw) and Fossorial Wasps. The sexes of the species with a very thin tegument, such as Apis, Bombus, and Vespa, can be quite easily distin- guished, as the rudiments of the genital armor can be seen through. The Hymenoptera are mostly confined to the warmer and temperate regions of the earth ; as we approach the poles, the Bees disappear, with the exception of Bombus, and perhaps its parasite Aixitlms ; a species of Vesixi is found on the Lab- rador coast, Avhich has a climate like that of Greenland. No fossorial species of Wasps are known to us to occur in the arc- tic regions, while a few species of Ants, and several Chalcidi- dce and Ichneumonidoi are not uncommon in Northern Labrador and Greenland. Our alpine summits, particularly that of Mt. Washington, reproduces the features of Northern Labrador and Greenland as regards its Hymenopterous fjiuna. The tropics are, however, the home of the Hymenoi)tera, and especially of the Bees. There are estimated to be about twenty-five thousand living species of this suborder, and this is probably a much smaller number than are yet to be discovered. In geological history, the Hymenoptera do not date far back compared with the Neuroptera and Orthoptera, and even the Coleoptera. Indeed they were among the last to appear upon the earth's surface. The lower forms, so far as the scanty records show, appeared first [n the Jura formation ; the Ants appear in the Tertiary period, especially in amber. As we have noticed before, the Hymenoptera are more purely terrestrial than any other insects. None are known to be aquatic in the early stages, and only two genera have been found 8 114 HYMENOPTERA. swimming in the adnlt state on the surface of pools, and thej' are the low, minute, degraded Proctotrupids, Prestivichia natans and Polynema nutans described by Mr. Lubbock. The Hymenoptera do not imitate or mimic the forms of other in- sects, but, on the contrary, tlieir forms are extensively copied in the Lepidoptera, and especially the Diptera. A partial excep- tion to this law is seen in tlie antennjTe of the Australian genus TJtaumatosoma, where they are long and slender, and knobbed as in the butterfly, and also in Tetralonia mirabilis of Smith, from lirazil. The Hymenoptera, also, show their superiority to all other in- sects in the form of their degraded wingless species, such as PezomacJuts, the workers of Formica and the female of Matilla. In these forms we have no striking resemblances to lower orders and suborders, but a strong adherence to their own Hymenop- terous characters. Again ; in the degradational winged forms, we rarely find the antennae pectinated ; a common occurrence in the lower suborders. In a low species of the Apiarim ^ Lamprocolletes dadocerus^ from Australia, — that land of anom- alies, — the antennjc are pectinated. This, Mr. F. Smith, the best living authority on this suborder, says, "is certainly the most remarkable bee that I have seen, and the only in- stance, to my knowledge, of a bee having pectinated antenna? ; such an occurrence, indeed, in the Aculeate Hymenoptera is onl}' known in two or three instances, as in Psammothenna Jlab- ellata amongst the 3Iatillidce , and again in Ctenocerus Klugii in the Pompilidce ; there is also a modification of it in one or two other species of Pompiilidce ." Among the Tenthre- dinidoi, the male Lopihyrus has well-pectinated antenuiie, as also has Cladomacra macropus of Smith, from New Guinea and Celebes. The wings of perhaps the most degraded Hymenoptera, the Proctotrujyidce, are rarely fissured; when this occurs, as in Pteratomus Patnamii, the}^ somewhat resemble those of Ptero- phoi'us, the lowest moth. It is extremely rare that the com- pound eyes are replaced by stemmata, or simple eyes ; in but one instance, the genus Anthophorahia^ are the eyes in the male sex reduced to a simple ocellus. This species lives in the darkness of the cells of Anthophora. APIARIiE. 115 By reason of the permanence of the type, due to the high rank of these insects, the generic and specific characters are founded on very sliglit ditterences, so that these insects, and particularly the two higher families, the Wasps ( Vesjndce) and Bees (^A2}(arice) are the most difficult insects to study. The easiest characters for the recognition of the genera, lie in the venation of the wings ; though in the fossorial families the legs vary greatl3^ The best specilic characters lie in the sculptur- ing and style of coloration, but the spots and markings are apt to vary greatly. The great differences between the sexes are liable to mislead the student, and hence large collections are indispensable for their proper study. Bees act as "marriage priests" in the fertilization of plants, convejing pollen from flower to flower, and thus insuring the formation of the fruit. It is said that many plants could not be fertilized without the interposition of Bees. Their interesting habits deserve long and patient stud}' ; it is for their observations on the insects of this suborder that the names of Reaumur, the two Hubers, aiid Latreille will be ever held in special remembrance. Most Hymenoptera love the sun, and they may be caught while flying about flowers. The nests of bees, wasps, and ants should be sought for and the entire colony captured, together with the parasites. The hairy species should be pinned while in the net, and the naked ones can be put in the collecting-bot- tle. The larger species may be pinned, like other insects, through the thorax; but the minute Chalcids, etc., should be gummed, like small Coleoptera, upon cards. The nests of bees and of wasps and ants and the 3'oiing in various stages of growth should be collected, and in such num- bers as to show their different stages of construction, to serve as illustrations of insect architecture. Apiari^ Latreille {Apidoe Leach). This and those families succeeding which are provided with a true sting, were called by Latreille Humenoptera Acideata. The male antennae are mostly thirteen-joiuted, while in the female the}^ are twelve- jointed. The females (and the workers, when they exist) feed the larvae, which mostly live in nests or cells. 116 HYMENOPTERA. In the social Bees, besides the normal male and female forms, there are asexual females, whose inner genital organs are partly aborted, though externally only differing in their smaller size from the true females. Tiie male antennae are longer, tapering more towards tlie tips, and the eyes of tlie male approach each other closer over the vertex than in the opposite sex, though these are characters wliich ai)ply to other Hymenoptera. The mouth-parts are in the higlier genera greatly elongated, the labium being long, with tlie lingua of great length, and the lobes of the maxilhe long and knife-shaped ; but these parts, as well as the form of the jaws, are subject to great modifications in the different genera : the labial palpi are four-jointed, and the maxillary palpi are from one to six-jointed. The hind tibia and basal joint of the tarsi are, in the pollen-gathering species, very broad ; the tibia is in Apis and Bombus hollowed on the outside, and stiff bristles project over the caA'ity from each side of the joint, forming the hone^'-basket (corbicuhnn), on which the "clodden masses of honey and pollen" are con- veyed to their nests. In the parasitic genera, such as Aixithiis, the tibia is, on the contrary, convex, rather than concave, though of the usual width ; while in Nomada, also parasitic, the legs are narrow, the tibia not being dilated. In Andrena and its allies, Ilalictiis and CoUetes, the mouth- parts, especially the tongue, are much shortened, thus afford- ing a passage into the Vesjiidce . In these genera the tongue is folded back but once between the horny encasement of the maxillae, but in the higher Ajiiarice the part formed by the union of the lingua and maxilla is twice bent back, and thus protected by the horny lobes of the maxillae. The fore- wings have two or three subcostal (cubital) cells. There are two thousand species of this family. The differ- ences between the larvai of the various genera of this family are very slight, those of the parasitic species are, however, readily distinguished from their hosts. The higher Aplarioi, comprising the subfamily ^Ij^miob, have the ligula long, c^dindrical, while the labial palpi have two very long, slender, compressed basal joints, and two short terminal joints. The genus A^ns has no terminal spurs on the hind tibiae, APIARIJE. 117 while the fore-wings have three subcostal (cubital) cells, the middle of which is elongated and acutely wedge-shaped. The eyes in the male are united above ; the mouth-parts are nearly aborted, and the hind legs are smooth. In the female there are two paraglossia on the ligula, and the maxillary palpi are one-jointed. The worker only difters externally from the female in the shorter abdomen. The larva of the Honey-bee closel}^ resembles that of Bom- bus, but the body is shorter, broader, and more flattened, while the head is less prominent, and the lateral tubercles along the body are, perhaps, less prominent than in the young Humble- bee, otherwise the two genera are, in the larval state, much alike. In its natural position, the larva lies at the bottom of the cell doubled upon itself. Though the larvne are said usually to feed upon pollen, Mr. Desborough states that honey alone is the food of the grub, as he reared 729 larvae with no other food than honey. But as with the wild bees they may extract honey from the pollen provided for them. He says the matured bees may be observed feeding at night on the bee-bread (pollen). Lang- stroth (The Hive and Honey-bee), hoAvever, states that "pol- len is indispensable to the nourishment of the young. It is very rich in the nitrogenous substances which are not contained in the honey." The Honey-bee, Apis meUiJlca, is now distributed over the civilized world. It was introduced into this country during the seventeenth century, and into South America in 1845 (Ger- stsecker). The Italian, or Ligurian, bee is considered by F Smith as being a climatic variety. The cultivation of the Honey-bee is rapidly increasing in this country, but the German Bee-masters have made the most pro- gress in theoretical and practical Bee-culture. Convenient hives are now constructed by which all the operations of the bees can be observed at leisure. Gerstfecker thus sums up the habits of the Honey-bee: A fertilized queen which, with a few workers, has wintered over, lays its eggs in the spring first in the worker, and afterwards, at a later period, in the drone- cells (both arranged in two perpendicular rows of cells). Early m summer, the workers construct the larger flask-shaped queen-. 118 HYMENOPTERA. cells, ■which arc plncecl on the edge of the comb, and in these the queen-larvae are fed with rich and choice nourishment. As soon as the first of the new brood of queens is exchuh'd from its cell, which it indicates by a peculiar buzzing noise, the old queen deserts the nest, canying away with her a part of the swarm, and thus forms a new colony. The recently excluded queen then takes its marriage flight high in the air with a drone, and on its return undertakes the management of the hive, and the duty of laying eggs. When another queen is disclosed, the same process of forming a new colony goes on. "When the supply of young queens is exhausted, the Avorkers fall upon the drones and destroy them without mercy. The first brood of Avorkers live about six wrecks in summer, and then give way to a new brood. Mr. J. G. Desborough states that the maximum period of the life of a worker is eight mouths. The queens are known to live five years, and during their whole life la}^ more than a million eggs (V. Berlepsch). Langstroth states that "during the height of the breeding season, she will often, under favorable circumstances, la}' from 2,000 to 3,000 eggs a day." According to Von Siebold's discovery only the queens' and workers' eggs are fertilized by sperm- cells stored in the receptacalum semoiis, and these she can fertilize at will, retaining the power for four or five jears, as the muscles guarding the duct leading from this sperm-bag are subject to her will. Drone eggs are laid by unfertilized queen-bees, and in some cases even by worker-bees. This last fact has been confirmed by the more recent observations of Mr. Tegetmeier, of London. Principal Leitch, according to Tegetmeier, has suggested the theory that a worker egg may develop a queen, if transferred into a queen-cell. "It is well known that bees, depri\'cd of their queen, select several worker-eggs, or very young larvtB, for the puqiose of rearing queens. The cells in which these eggs are situated are lengthened out and the end turned down- ward." He suggests that the development into a queen was caused by the increased temperature of the queen-cell, above that of the worker-cells. But Messrs. F. Smith and Woodbury (Proceedings of the Entomological Society of Loudon, January 2, 1862) support F. APIARI^. Ug Huber's theory, thnt the change is due to "the quality as well as quantity of food with which the royal larva is supplied," though Dr. Leitch objects, that it has been by no means con- chisively proved "that the so-called royal jelly differs in any respect from the ordinary food supplied to the worker larva;" and Mr. Woodbury cites the experiments of Dzierzon, as quoted by Kleine, "that as Huber, by introducing some royal jelly in cells containing worker-brood, obtained queens, it may be possible to induce bees to construct royal cells, when the Apiarian prefers to have them, by inserting a small portion of royal jelly in cells containing worker-larvsB." Kleine takes " an unsealed royal cell — which usually contains an excess of royal jelly — and removes from it a portion of the jelly, on the point of a knife or pen, and by placing it on the inner margin of any worker cell, feels confident that the larviB in them will be reared as queens." Before these points are settled we must study the habits of the Wild Bees, and of the other social Hymenoptera and White Ants, together with the social Aphides more carefully, Mr. F. W. Putnam pertinently states, "at present I cannot believe that the peculiarity of food, or the structure of the cells, pro- duces a difference of development in Humble-bees, for the lar- vae, as has been previously stated, were seen to make their own cells from the pollen paste. Is it not more natural to believe, as has been suggested to me by Professor J. Wyman, that the difference in the development of the eggs is owing to their be- ing laid at various times after impregnation ? Thus, if I am right in supposing that the queens are impregnated by the males late in the summer, the eggs, laid soon after, produce the large queen larvse ; * the next set of eggs, laid in the spring, produce the workers, or undeveloped females, while from those deposited still later, male bees are principally developed." (Proceedings of the Essex Institute, Salem, vol. iv, 18G4, p 103.) Referring to Mr. Putnam's statement that there are both small and large queens (besides the workers) , Dr. Gerstoecker infers, *Dr. Gerstsecker, on the other hand, states that "from the brood-cells of a nest of Bombutt muscorum, found by him on tlie 18th of September, there were devel- oped at the end of the same mouth only workers." 120 HYMENOPTERA. "from the examination of numerous individuals found flying in tlie spring after hibernation, tliat tliese could not be considered as true queens, since tlieir ovaries were only moderately devel- oped, though larger than tliose of the workers, while in the true queen, captured in the sinnmer, the ovaries were perfectly developed. Tliis corresponds almost entirely to what we find in the wasps, Avhose spring females have only moderately de- veloped ovaries." How the Ilonej'-bee builds its cells, and whether they are ex- actly hexagonal, are questions that have interested the best observers from Maraldi who wrote in 1712, and Reaumur, whose Memoires appeared in 1740, down to the present date. Their solution involves not only the closest observation of the insect while at work, but also the shrewdest judgment to ex- plain the facts observed and deduce a legitimate theory. Does the bee intelligently plan her work out beforehand, or does she follow the guidance of what is called instinct? Does she construct hexagonal cells which are mathematicall}'' exact, or does she vary the proportions of each cell, so that it is per- fect only in its general ideal form? Again, in making the cell, is the bee actually capable of making such a cell alone, or is it due to the resultant action of several bees? Professor J. Wy- man is of the latter opinion, as he thinks "that if left alone to build a single cell, this would most probably be round. In the cells of Mdipona^ as Huber's plate shows, they are only hex- agonal when in contact Avitli the adjoining cells." (Proceed- ings of the Boston Society of Natural Histor^^, x, p. 27(S, 186G.) A similar view is tliat proposed in 1862 b}" the Rev. Samuel Haughton, in a paper read before the Natural History Society of Dublin, where he says, according to Mr. F. Smith, that the hexagonal form of the cell " may be accounted for simply by the mechanical pressure of the insects against each other during the formation of the cell. In consequence of the instinct that compels them to work with reference to a plane, and of the cylindrical form of the insect's body, the cells must be hex- agonal." Mr. G. R. Waterhouse (Transactions of the Entomological Society of London. Third series, vol. ii, p. 129, 1864) lias APIARI^. 121 proposed what has been called the "circular theory," or \vh:it the author himself terms "the principle of working in seg- ments of circles." He contends " that tlie hexagonal form of the cells of certain bees and wasps may, and does, arise out of this mode of action when under certain conditions ; that those condi- tions are, that the cells are so commenced that their natural cir- cumferences, as the work proceeds, are either simply brought into contact with each other, or that the cells are so placed tliat the (we Avill say theoretical) circumferences must intersect. Contact with adjoining cells, then, is an essential condition to bring about the hexagonal form as I have before pointed out (See Proceedings of the Entomological Society, 1858, p. 17) : but for this result it is not necessary that a hexagonal cell should be completely surrounded by other cells." Is not this theory, after all, too mechanical ? Is not our liee more of a free agent ? Does it not have a mind to design its work? Mr. F. Smith, Avho has devoted years to the study of Hymenoptera, especially the higher forms of this suborder, the Bees and Wasps, replies to both theories of Waterhouse and Haughton, by bringing in the case of the Wasps which also build hexagonal cells, showing that a solitary wasp will build its cells in very regular hexagons. Thus the nest of the soli- tary Wasp, Icaria guttatipennis^ "consists of a double row, the number of cells being ten ; I now direct your attention to the fact that all the cells are perfectly hexagonal, the exterior planes being as beautifully finished as those in contact with the inner planes of the opposing cells. I have placed a draw- ing of this nest (Plate 5, Fig. 7) in the box on the table, and I particularly wish you to observe, that the first cell is carried up in a perfectly hexagonal form aboA'e the adjoining cells ; n proof that, if Wasps never build perfect isolated hexagonal cells, they certainly possess the capability of doing so. The exterior of all the cells, as I before observed, is hexagonal, not cylindri- cal, until fresh cells are added on the outer side, as was ob- served to be the case in combs of the Hive-bee, by Mr. Tegetmeier." (Proceedings of the Entomological Society of London. Third series, ii, 1864, p. 135.) An examination of the cells of three species of PoUstes (the female of which begins alone in the spring to build her nest 122 HYMENOPTERA. the cells of which are afterwards greatly increased in numljer after the first brood of females appear), convinced us that the Wasp begins with the circular cup-shaped form of cell, and when about depositing an egg in it, changes her mode of ope- ratiu"', builds up the edges into a liexagonal form, and carries up the rim of each cell independently to its required height. She thus apparently changes her plan at a certain stage of the work, and is so far a free agent. Mr. Smith also exhibited a portion of the nest of another wasp, Tatua Morio (Plate 5, Fig. 9), that proved to his mind the primary intention of the wasp instinctively to build cells with exactly six sides. The figure represents part of one of the flat floors, on which the foundations of the cells are laitl in regular hexagons, instead of beginning in hemispherical cups. Mr. Smith (p. 141) concludes, "that all hexagonal cells are not constructed upon a circular principle, and that the primary idea of all social bees and wasps is not to produce cylindrical cells with hemispherical bases." In this connection the following extract from Mr. Smith's remarks is of interest : "It may not be known that in order to expedite the building of honey -combs, it is a common practice with bee-keepers in Germany to furnish hives with artificial foundations for the cells ; these consist of sheets of wax, upon which is impressed a series of pyramidal hollows ; in fact, the counterpart of a comb built by the bees themselves, entirely deprived of the cell-walls ; and it is from such a piece of comb that the casts for the artificial foundations are obtained. A piece of casting of this description I lay before you, and I par- ticularly call your attention (addressing the members of the Entomological Society of London) to the commencement of the outer cells ; you will see, in some instances, a single plane of the hexagonal cell commenced, in others two or three are in progress ; here you have a ground-plan supplied, or, I may say, the foundations of the habrtations ready prepared, upon which the laborers are to raise the walls, and j'ou nuxy see how admi- rably they have done it. Instinct enables the bee to construct hexagonal cells without teaching, and, we are told, in one un- ileviating manner. Surely the example before us exhibits an amount of intelligence on the part of the bees in availing them- APIAUI^. 123 selves of such adventitious aid. Must we not henceforth, when speaking of the marvels of the liive or the vespiary, erase from our vocabulary such terms as blind instinct ; and must we not cease to stigmatize the bee as a mere machine ? " At the meeting of the same society held Feb. 1, 1864, Mr. F. Smith exhibited a collection of Wasps' nests, — one of Vesjm rufa, the rest of V. vulgaris; they were in various stages of formation, the earliest consisting of only a single cup contain- ing the first egg, others consisting of three or four cups, whilst others again were more complete. The whole had been arti- ficially obtained by Mr. Stone, who tempted the wasps to build by excavating holes in banks and furnishing them with foot- stalks ; in fact, Mr. Stone appeared to possess the power of inducing wasps to build nests of almost any shape he pleased. But to return to the cell of the Bee. It should first be proved that the cells are not exactly and mathematically per- fect hexagons, though sufficiently so for the purpose for which they are used. In the Proceedings of the American Academy of Arts and Sciences, vol. vii, 1866, Professor Wyman has, by a most careful as well as novel and ingenious mode of investiga- tion, proved that the cells are all more or less imperfect, and that a hexagonal cell mathematically exact, does not exist in nature, but only in theory. The form of the cell is liable to marked variations, chief among which the following may be mentioned, in the author's own words : "1. The diameters of workers' cells may so vary, that ten of them may have an aggregate deviation from the normal quantity equal to the diameter of a cell. The average varia- tion is a little less than one half that amount, namely, nearly 0.10 inch, in the same number of cells. '•2. The width of the sides varies, and this generally in- volves a variation of the angles which adjoining sides make with each other, since the sides vary not only in length but in direction. "3. The variation in the diameters does not depend upon accidental distortion, but upon the manner in which the cell was built. 124 HYMENOPTERA. "4. The relative size of the rhombic faces of the pyramidnl base is liable to frequent variation, and this where the cells are not transitional from one kind to another. ''o. When a fourth side exists in the basal pyramid, it may be in consequence of irregularity in the size of the cells, or of incorrect alignment of them on the two sides of the comb." Sometimes one of the faces is lost, and a new one formed, so that all the basal portion of the cell becomes reversed, as ABC will be seen by refer- ence to F'igs. 73 and 74 ; the first repre- Fis- 73. senting the cells when the base is viewed, and the second when looked at perpendic- ularly to one of the sides. In both figures A indicates the ordinary form of the cell. The whole a b c series of Fig. 74 shows the gradual introduction of the new face, which is seen on the lower border, and the elimination of one of the original faces, which is seen on the upper border. At B, Avhich is intermediate between the Fig. 74. two extremes, the four faces consist of two equal rhombs, — one of which is the outgoing and the other the incoming one, and two equal hexagons. B, Fig. 74, represents the sides of the same cell, which, instead of forming three trapeziums, as at A, a, 6, c, now form two pentagons, a' and c', and a parallelogram, h'. At C, Figs. 73 and 74, the forms are in all respects the reverse of those of A. A and C are symmetrical with each other, and B is symmetrical in itself. No pre- cise number of cells is necessary for the purpose of making this transition, for it may take place in two or three, or extend through a long series, as in Fig. 73. " G. Ordinarily, the error of alignment does not amount to more than one or two diameters of a cell. But occasionally V C" Fis. 75. APIARI^. 125 --/ the rows of cells on one side of the comb may deviate from tlieir true direction with regard to those on the other, to the extent of 30°." "Thus, if a piece of normal comb be held in the position in which it was built, two of the opposite angles of the hexagon. Fig. 75, A, a, will be in the same vertical line, and two of the sides will be parallel to this. The same is true of the opposite side of the comb ; and thus all the cor- responding parts of the cells on the two sides will be par- allel. In the deviation we are now noticing, the change is like that represented in A, where the cell a is in its true position, while the cell h, which is from the oppo- site side, and is in contact with o, varies from it by about 30°. If we look at these two cells in the direc- tion of their sides as at B, the prism a will have one of its angles towards the eye, and b one of its sides. In consequence of this deviation and the continual crossing of the rows on opposite sides, the pyramidal base is not made, and the cell is shortened. " 7. In curved or bent combs the cells on the concave side tend to be- come narrower, while those on the other tend to become broader to- wards their mouths. In Fig. 76 (this and Figs. 77 and 78 are made ^'^- '^'^' from impressions obtained directly from the comb and transferred to wood ; they represent the form of the cells exactly), as in the central line of cells, there are a variety of hexagons, each resulting from the union ff Fisr. 76. 126 HYMENOrXERA. of two cells, the base being double while the mouth is single. That on the line a, b, has three sides at one end, united by two long sides with one at the other, and thus two of the opposite sides are not parallel ; at c, d, two sides at a b c d e f Fig. 78. either end are united by two long sides, these last being par- allel ; and at e, /, the mouth of the compound cell has seven sides. Each has a partition at its base, separating the two originally distinct cells, and each was lined with a cocoon, showing that it had been used for rearing young. At j/, not only has the partition between the combining cells disappeared, but also three of the sides of each cell." The bees do not appear to have any systematic w^ay of mak- ing a transition from worker to drone cells, which are one-liftli larger than the former. ]\Iore connnonly, they effect it by a gradual alteration of the diameters, thus enlarging a worker into a drone, or narrowing a drone into a worker cell. This alteration is usually made in from four to six rows. In one case APIARI^. 127 Professor Wyman noticed the transition made with only one cell, as in Fig. 78, but not without destro3'ing the regularity- of the two adjoining rows. " In consequence of the gradual narrowing or widening of the transition cells, the comb tends to become more or less tri- angular and the cells to become disturbed. The bees counter- act this tendency by the occasional intercalation of an additional row, of which two instances are given in Fig. 78, at a and b^ where three rows of worker cells are continuous with two of drone cells, c, d and e, /; or, reversing the statement, and supposing the transition, as in the building of the comb, is from worker to drone-cells, a row of the latter is from time to time omitted as the rows a and h ; in this wa}-, the regularity of the comb is preserved." Ilone^'-cells are formed either by enlarging the ordinary brood-cells, or adding them to others often larger, or b}^ con- structing a new comb, devoted entirely to the storing of honey. "While the cells of this last are built unequivocally in accord- ance Avitli the hexagonal type, the}' exhibit a range of variation from it which almost defles description." No Ichneumon-flies are known to attack the larva of the Honey-bee, nor in fact, with few exceptions, any of the wild bees, owing, probably, to the difficulty of their gaining access to them, since Anomalon vesparum has been reared from the cells of wasps which are more exposed than those of bees. But the Honey, as well as the Avild bees, are afflicted by a peculiar assemblage of insect-parasites, some of which have tlie most remarkable habits. The most formidable pest of the Hive-bee is the Bee Fly, Phora incrassata, Avhich in Europe sometimes produces the well-known disease called "foul- brood." The Bee-louse, Braula cwca, is, in Europe, sometimes troublesome to the adult bee, while Trichodes apiarius, a beetle, devours the larvae. The larvtie of Meloe and Stylops are known in Europe to infest the Honey-bee, and among the low intesti- nal worms Assmus enumerates Gordius suhhifarcus which in- fests the drones of the Honey-bee as well as other insects. Professor Siebold has also described Mermis albicans^ which is a similar kind of hair-worm, from two to five inches long, and whitish in color. This worm is also found, strangely 128 IIYMEXOPTEKA. eiiougli, only in the drones, tliongh it is the workers which frequent watery pLaces (where the worm deposits its eggs) to appease their thirst. The "Wax-motlis, Galleria cereana and Acliroia alvearia, do much harm by consuming the wax and thus breaking down the cells, and by filling the hive with their Avebs.* The genus A2)is is indigenous in South America, though the Honey-bee has been extensively introduced into the West In- dies. Our Honey-bee is replaced in tlie tropics by the stingless, minute bees, Avliich store up honey and live in far more numer- ous colonies. The cells of MeUjiona are hexagonal, nearly approaching in regularity those of the Hive-bee, while the honej'-cells are irregular, much larger cavities, which hold about one-half as much honey as a cell of the Humble-bee. From a ])aper on the Brazilian Honey-bees, read by Mr. F. Smith be- fore the Entomological Society of London, March, 18G3, he states that the Meliponas are small insects, having wings shorter than the abdomen, the latter being ver}' convex and oblong ; their mandibles never being dentate ; while the Trkjonas have the wings more ample, and longer than the abdomen, which is short, somewhat triangular, while the mandibles are serrated, denticulate, or sometimes edentate. The 3IeIiponas are re- stricted to the new world, while Trigona extends into Africa, India, and Australasia. "All these bees are honey gatherers, but the honey collected by the different species varies greatly in quality : from the nests of some it is excellent ; from others, worthless. The honey of the species ^ Momhuca' is said to be black and sour, the quality being dependent on species of flowers from which the honey is collected. This great difference in the honey of the various species is apparent^ confirmatory of the fact that each species confines itself to particular flowers, never visiting any other kind. The different relative length of the tongue in ♦Explanation of Plate 2. Parasites of the Honey-ljee. Fig. 1, Phora incras- sata; Fig. 2, pupa; Fig. 3, larva. Fig. 4, Braula cceca; Fig. 5, larva. Fig. 6, Tri- chodes nplarius .- a, larva ; b, pupa. Fig. 7, Meloe. angustlcollis ; Fig. 8, freshly hatched larva; Fig. 9, second stage of larva; Fig. 10, first stage of semi-pupa; Fig. 11, pupa. Fig. 12, Stijlops Chihlreni in the body of a wild bee, Andrena; Fig. 13, top view of the same removed from its host; Fig. 14, male of the same; a, side view. Fig. 15, Mncor meUitophorus, a parasitic fungus. Fig. 16, unknown larva found in uest of Humble-bee. Descriptions of the insect parasites will be given beyond. Plat ft 2 Fi?. 1. Fig. n. Fig. ; Fis. r.. Fig. 4. Fig. 13. PARASITES OF THE HONEY BEE. APIARI.E. 129 the species is also confirmatory of the same supposition ; in- deed, tlie great diversity in tliis respect observable in tliese l)ees, appears to me to be analogons to a similar diversity in the length of the bills of hunnning-birds, whicli, it is uell known, are always adapted for reaching the nectaries of the particular flowers which they usually frequent." In regard to tlie imnrense numbers of individuals in a col- ony, Mr. Stretch, who collected them at Panama, "found a nest several feet in lengtli in the hollow of a tree, containing thousands of individuals, their numbers being, as he informs me, apparently countless. "Gardner, in his travels, gives a list of such species (of Melipona) as he met in the provinces of Piauliy and Goyaz, where he found them numerous; in every house, he says, 'you find the honey of these l)ees ;' many species, he tells us, build in tlie hollow trunks of trees, others in banks ; some suspend their nests from branches of trees, whilst one species constructs its nest of clay, it being of large size ; the honey of this spe- cies, he says, is very good." (Smith.) In a nest of TrUjoiui carbonaria from Eastern Australia, Smith, of the British Museum, found from 400 to 500 dead workers crammed in the spaces between the combs, but he did not find a female among them. The combs are arranged precisely similar to those of the common wasp. The numl)er of lioney-pots, which are placed at the foot of the nest, amounted to 250. Smith inclines to the opinion that the hive of Trigona con- tains several prolific females ; "the accounts given of the nuil- titudes inhabiting some nests is too great, I think, to render it possible that one female could produce them all. Sir. Stretch described a hive that he saw, occupying the interior of a decay- ing tree, that measured six feet in length, and the multitude of l)ees he compared to a black cloud. M. Guerin found six fe- males in a nest of Melipona fnlvipes.'" Hill states, in Gosse's Naturalist's Sojourn in Jamaica, "that the wax of these bees [Trigona] is very unctuous and dark colored, but susceptible of being whitened by bleaching. The honey is stored in clusters of cups, about the size of pigeon's eggs, at the bottom of the hive, and always from the 9 100 HYMEXOPTEPtA. brood-cells. The hrood-cells are hexagonal ; thej^ are not deep, and the young ones, ■when ready to burst their casement, just liU tlie whole cavity. The mother bee is lighter in color than the other bees, and elongated at the abdomen to double their length." .Smith also states that the female of this genus has the abdomen greatly distended, reminding one of the gravid female of the White Ant. (Smith, Proc. Ent. Soc, London, Dec. 7, 18G3.) In North America, our nearest ally, as regards its habits, of the true Honey-bee, is the Humble-bee {Bo7nbi(s), of which over forty species are known to inhabit North America. The economy of the Humble-bee is thus : the queen awakens in early spring from her winter's sleep beneath the leaves or moss, or in deserted nests, and selects a nesting-place generally in an abandoned nest of a field-mouse, or beneath a stump or sod, and "immediately," according to Mr. F. W. Putnam, "collects a small amount of pollen mixed with hone3^ and in this deposits from seven to fourteen eggs, gradually adding to the pollen mass until the first brood is hatched. She does not wait, however, for one brood to be hatched before laying the eggs of another ; but, as soon as food enough has been collected, she lays the eggs for a second. The eggs [Plate 4, Fig. 2] are laid, in contact with each other, in one cavity of the mass of pollen, with a part of which they are slightly covered. They are very soon developed ; in fact, the lines are nowhere dis- tinctly drawn between the egg and the larva, the larva and pupa, rnd again between the latter and the imago ; a perfect series, showing this gradual transformation of the young to the imago, can be found in almost every nest. "As soon as the larvie are capable of motion and commence feeding, they eat the pollen by which they are surrounded, and, gradually separating, push their way in various directions. Eating as they move, and increasing in size quite rapidly, they soon make large cavities in the pollen mass. When they Lave attained their full size, they spin a silken wall about them, which is strengthened by the old bees covering it with a thin layer of Avax, which soon becomes bard and tough, thus form- ing a cell. [Plate 4, Figs. 1, 2.] The larviia now gradually attain the pupa stage, and remain inactive until their full devel- Plate a. PARASITES OF WILD BEES. APIARIvE. 1;j1 o'pmcnt. They then cut their way out, and are ready to assume their duties as workers, small females, males or queens, "It is apparent that the irregular disposition of the cells is due to their being constructed so peculiarly by tlie larva?. After the first brood, composed of workers, has come forth, tlie queen bee devotes her time principally to her duties at home, the workers supplying the colony with honey and pollen. As the queen continues prolific, more workers are added, and the nest is rapidly enlarged. "About the middle of summer eggs are deposited which produce both small females and males." . . . "All eggs laid after the last of July produce the large females, or queens ; and, the males being still in the nest, it is presumed that the queens are impregnated at this time, as, on the api)roacli of cold weather, all except the queens, of which there are several in each nest, die." (Putnam, Com. Essex Inst., vol. iv, p. 98, 1864.) Besides Apathus, the larvae of various moths consume the honey and waxen cells ; the two-winged flies, Volucella and Conops, and the larv;e of what is either an Anthomyia or Tachina-like fly ; several species of Anthrax, the Coleopterous Anobium paniceum of Europe, Meloe, Stylops, and Anthero- phagus ochraceus are parasitic on Humble-bees.* The habits of the genus Apathus are not clearly known, but they are supposed to prey, in the larva state, upon the larviie of Bombus, being found in their nests ; their habits, so far as known, ally them with Nomada. The species are distinguished by the tibite being convex, instead of concave, as in Bombus, while the mandibles of the females are acute, triangular, biden- tate, being spatulate and three-toothed in Bombus, and they have no pollenigerous organs. There are males and females only, as in all the remaining genera of the family. Ajmlhus Ashtonii (Plate 3, Fig. 1) is found in the Northern States. * Explanation of Plate 3. — Parasites of the Humble and Lcaf-cutfer Bees. Fig. 1, Apathus Ashtonii. F'v^.'i, Nephopterijx Eilmavdsiii «, larva; 6, pupa. Fig. 3, 3rt, Micror/aster nephoptericis, an Ichneumon parasite of Nephopteryx. Fig. 4, Jiitherophiif/us ochraceus. Fig. 5, Anthomijia'i larva; a, side view. Fig. 6, Re- cently hatched larva of Stylops Childrenii; a, side view. Fig. 7, larva; «, pupa of Anthophorabia viegnchilis, a Chalcid i)arasite on Megachile. Fig. 8, Pteratomus Putnamii, an exceedingly minute Proctotrnpid fly, supposed to be parasitic on An- thorphorabia mcgacliilis; a, a hind wing. P'ig. 9, a Mite found iu the nests of liiimble-bees. 132 HYMENOrTEKA. Xylocopa, the Carpentcr-liee, is "the hiri^jest and most l:)nlky of a.11 known bees," but less hirsute tluin Bombus, wliile tlie basal joint of tlie labial palpi is almost four times as long as the second ; and the maxillary palpi are six-jointed, the mouth- parts being veiy highly organized. The larva of X. Virginica (Plate 4, Fig. 3, adult ; Fig. 4, larva ; Fig. 5, nest) is slenderer than that of Bombus, the body tapering more rapidly towards each end. The power of boring the most symmetrical tnnnels in solid wood reaches its perfection in the large Virginian Carpenter- bee {^Xylocopa Vlnjinica). We have received from Mr. James Angus, of West Farms, N. Y., a piece of trellis for a grape- vine, made of pine wood, containing the cells and yonng in various stages of growth, together with the larvce and chrysa- lids of Anthrax sinuosa (Plate 4, Fig. 6, larva; Fig. 7, pupa), a species of fly parasitic on the larva of the bee, and which buries its head in its soft bod}' and feeds on its juices. Mv. Angus thus writes us regarding its habits, under date of J d}- 19 : "I asked an intelligent and observing carpenter jcs- terday, if he knew how long it took the X^docopa to bore hor tunnel. He said he thought she bored about one-quarter of an inch a day. I don't think myself she bores more than one- half inch, if she does that. If I mistake not, it takes her about two days to make her OAvn length at the first start ; but this being across the grain of the wood may not be so easily done as the remainder, which runs parallel with it. She always follows the grain of the wood, with the exception of the en- trance, which is about her own length. The tunnels run from one to one and a half feet in length. They generally run in opposite directions from the opening, and sometimes other gal- leries are run above the first, using the same opening. I think they onl^' make new tunnels when old ones are not to be found, and that the same tunnels are used for many years. Some of the old tunnels are very wide. I have found parts of them about an inch in diameter. I think this is caused by rasping off the sides to procure the necessary material for con- structing their cells. The partitions are composed of wood- raspings, and some sticky fluid, probably saliva, to make it tidliere. apiari.t:. 133 "The tunnels are sometimes taken possession of by other bees and wasps. I tiiink when this is the case, the Xylocopa prefers making a new cell to cleaning ont the mud and rubbish of the other species. I frequently find these bees remaining for a long time on the wing close to the opening, and bobbing their heads against the side, as if fanning air into the opening. I liaA-e seen them thus employed for twenty minutes. Whether one bee, or more, makes the tunnel, that is, whether they take turns in boring, I cannot say at present. In opening the cells, more than one are generall}' found, even at this season. About two weeks ago, I found as many as seven, I think, in one." * The hole is divided by partitions into cells about seven-tenths of an inch long. These partitions are constructed of the dust or chippings made by the bee in eating out her cells, for our active little carpenter is pro^"ided Avith strong cutting jaws, moved by powerful muscles, and on her legs are stiff brushes of hair for cleaning out the tunnel as she descends into the heart of the solid wood. She must throAV out the chips she bites off from the sides of the burrow Avith her hind legs, pass- ing the load of chips backwards out of the cell with her fore- limbs, which she uses as hands. The partitions are built most elaborately of a single flattened band of chips, which is rolled up into a coil four layers deep. One side, forming the bottom of the cell, is concave, being * " Since writing the above I have opened one of the new holes of Xylocopa which was conimenced between three and four weeks ago, in a pine slat used in the staging: of the greenhouse. Tlie dimensions were as follows: Oitening fully 3-S wide ; dei)tli 7-10 ; whole length of tunnel G and 5-10 inches. The tunnel branched both ways from the hole. One end, from opening, was 2 and fl-S, containing three cells, two with larva and pollen, the third empty. The other side of the opening, or the rest of the tunnel, was empty, with the exception of the old bee (only one) at work. I think this was the work of one bee, and, as near as I can judge, about twenty-five days' work. Width of tunnel inside at widest 9-10 mch. For some days this bee has been discharging a great quantity of saw-dust and l)ollen, which I had collected by iilacing a vessel under it. It would seem that she liad cells constructed also in tlie oiiposite side of the hole, and that she removed them to enlarge the tunnel. Among the stuff thrown out, I find a partition of a cell nearly entire. I have just found a Xylocopa bobbing at one of the holes, and in order to ascer- tain the deiith of the tunnel, and to see whctlier there were any others in them, I sounded with a itliable rod, and found others in one side, at a depth of five and one half inches ; the other side was four inches deep, without bees. The morning was cool, so that the object in bobbing could not be to introduce fresh currents of air, but must have had some relation to those inside. The legs on such occasions are, as 1 have noticed, loaded with pollen.-'— American Naturalist, vol. 1, p. 370. 134 HYMENOPTERA. beaten down Jind smoothed olT by the bee. The other side of the partition, forming the to}) of the cell, is Hat and rongh. At the time of opening the burrow, July 8th, the cells con- tained nearly full-grown larvae, with some half developed. They were feeding on the masses of pollen, which were as large as a thick kidney-bean, and occupied nearly half the cell. Sa- pyga repanda is parasitic in the cells of Xylocopa violacea of Southern Europe. The habits and structure of the little Ceratina ally it closely with Xylocopa, as it hollows out the stems of plants, and builds in them its cylindrical cells. This bee is oblong in form, with tridentate mandibles, and a short labrum. The maxillary palpi are six-jointed, and the labial palpi are two-jointed. Ceratina diipla Say is a common small bright-green smooth-bodied species, which, in the middle of May, according to Dr. Harris' MS. notes, tunnels out the stems of the elder or blackberry, syringa, or any other pithy shrub, excavating them often to a depth of six or seven inches, and also, according to Mr. Haldeman (Harris MS.), bores in Cocorus. She makes the walls just wide enough to admit her bod}', and of a depth capable of holding three or four, often five or six cells (Plate 4, Fig. 11). The finel}' built cells, with their delicate silken walls, are cylindrical and nearly square at each end, though the free end of the last cell is rounded off. They are four and a half tenths of an inch long, and a little over one-third as broad. The bee places them at nearly equal distances apart, the slight interval between them being filled in with dirt. Dr. T. AY. Harris* states that, "May 15, 1832, one female laid its eggs in the hollow of an aster-stalk. Three perfect in- sects were disclosed from it July 28th." The observations of Mr. Angus, who saw some bees making their cells, May 18th, also confirms this account. The history of our little upholsterer is thus cleared np. Late in the spring she builds her cells, fills them Avith pollen, and lays one or more eggs upon each one. Thus in about two months the insect completes its transforma- tions ; within this period passing through the egg, the larval and chrysalid states, and then, as a bee, living through the win- ter. Its life thus spans one year. * Aocoi-iling to a note iu ISISS. deposited in the Libi-ary of the Boston Societj' of Natural History. APIARLT^]. 135 The larva (Plate 4, Fig. 10) is longer tlian that of Mega- chile, and comjiared with that of X^loeopa, the ditferent seg- ments are much more oomex, giving a serrate outline to the back of the worm. The i)U[)a, or chrysalis, we have found in the cells the last of July. It is white, and three-tenths of an inch long. It differs from that of the Leaf-cutter bee in having ibur spines on the end of the body, and in having a much longer tongue and maxillae, both being almost twice as long. In none of the wild bees are the cells constructed with more nicety than those of our little Ceratina. She bores out with her jaws a long dee]) well just the size of her body, and then stretches a thin delicate cloth of silk, drawn tight as a drum- head, across each end of lier chambers, which she then fills with a mixture of pollen and honey. Her young are not, in this supposed retreat, entirely fi-ee from danger. The most invidious foes enter and attack them. Three species of Ichneumou-tiies, two of which belong to the Chalcid family, lay their eggs within the body of the larva, and emerge from the dried larva and pupa skins of the bee, often in great luunbers. The smallest parasite, belonging to the genus Anthophorabia (so called from being first known as a parasite on another bee, Authophora), is a minute species found also abundantly in the tight cells of the Leaf-cutter bee. The species of Anthkh'nm, according to Smith, are gaily marked with yellow bands and spots ; the ligula is almost twice as long as the labial pali)i, and acutely pointed ; the paraglossa? are short, the maxillary palpi are two-jointed, and there are two subcostal cells. Tlie males are longer than the females, with an elongated and stoutly toothed abdominal tip. Tlie female lines her nest, situated in any hole convenient for its purpose, with down from woolly-stemmed plants. They pass the winter in the larva state, and the bees do not appear until mid-summer^ The species mostly occur in the old world. In Ajithojihoni, which approaches nearer to Bombus in its plump and hairy body than the two preceding genera, the lig- ula is twice as long as the labial maxilhi?, ending in a bristle- like point ; the basal joint of the hind tarsus is thickly hirsute, while the middle tarsus of tlie males is generally elongated. The species are gregarious, their numerous cells, while indepen- 136 HYMENOPTERA. (lent, are croAvded togctlier in grassy banks. Species of Melecta are parasitic on them, ovipositing in their cells. The larviie are infected by tlie Chalcid flies, Anthophorabia and Monodontomerns, and ])y a peculiar species of Mite, Hete- ropus ventricosus, described by Newport. Say has described Anthophora ahrupta and ^1. taurea from Indiana. In Eacera the antenna? are very long, while the body is still plump and hairy : our more common form in the Middle States is Eacera macalata St. Fargeau. The species are likewise gregarious, and, according to Smith, their habits are precisely the same as those of Anthophora. In 3Ie(jachile, the Leaf-cutter Bee, the head is broad, the body stout, oblong, the ligula is about one-half longer than the labial palpi, being quite stout, while the paraglossre are short and pointed ; the maxillte are long and sabre-shaped, while their palpi are short and two-jointed. There are two subcostal cells in the fore wing. It is a thick-bodied bee, with a large square head, stout scissor-like jaws, and with a thick mass of dense hairs on the under side of the tail for the pur- pose of carrying pollen, since it is not provided with a pollen basket as in the Honey and Humble-bees. The larva is broader aiid flatter than that of Bombus, the raised pleural region is a little mor-j prominent, and the raised, thickened tergal portion of each ring is more prominent than in Bombus. The Megachile lays its eggs in burrows in the stems of the elder (Plate 4, Fig. 9), which we have received from Mr. James Angus ; Ave have also found them in the hollows of the locust tree.' Mr. F. W. Putnam thus speaks of the economy of M. centuncidaris^ our most common species. "My attention was first called, on the 2Gth of June, to a female busily en- gaged in bringing pieces of leaf to her cells, Avhich she Avas build- ing under a board, on the roof of the piazza, directly under my Avindow. Nearly the Avhole morning Avas occupied by the bee in bringing pieces of leaf from a rose-bush groAving about ten yards from her cells, returning at intervals of a half minute to a minute Avith the pieces Avhich she carried in such a manner as not to impede her Avalking Avhen she alighted near her hole. [We give a figure of the Leaf-cutter bee in the act of cutting out a circular piece of a rose-leaf (Plate 4, Fig. 8). She alights upon the leaf, and in a few seconds swiftly rnns lier scissors-like jaws around through the leaf, bearing off the piece in her hind legs.] About noon she had probably com- pleted the cell, upon which she had been engaged, as, during the afternoon, she was occupied in bringing pollen, preparatory to laying her single egg in tlie cell. For about twenty days the bee continued at work, building new cells and supplying them with pollen. ... On the 28th of July, upon removing the board, it was found tliat llie bee had made thirty cells, arranged in nine rows of unequal length, some being slightly curved to adapt tlicm to the space under the board. The longest row contained six cells, and was two and three-quarters inches in length ; the whole leaf-structure being equal to a length of fifteen inclics. Upon making an estimate of the pieces of leaf in this structure, it was ascertained that there must have been at least a thousand pieces used. In addition to the labor of making tlie cells, this bee, unassisted in all her duties, had to collect the requisite amount of pollen (and honey?) for each cell, and lay her eggs therein, when com- pleted. Upon carefully cutting out a portion of one of the cells, a full-grown larva was seen engaged in si>iuniug a slight silken cocoon al)out the walls of its prison, which were quite hard and smooth on the inside, probably owing to the move- ments of the larva, and the consequent pressing of the sticky particles to the walls. In a short time the opening made was closed over by a very thin silken web. The cells, measured on the inside of the hard walls, were .35 of an inch in length, and .15 in diameter. The natural attitude of the larva is some- what curved in its cell, but if straightened, it just equals the inside length of the cell. On the 31st of July, two female bees came out, having cut their way through the sides of their cells." In three other cells "several hundred minute Ichneu- mons [Anthophorabia megachilis] were seen, which came forth as soon as the cells were opened." (Com. Essex Inst., vol. iv, p. 105, 1864.) Megacldle integer Say IMS., according to Dr. Harris (MS. notes), forms its nest of leaves the first of August. This spe- cies is twice as large, but closely resembles 3k'gaeliiJe hrevis of Say. The front of the head is covered with dense ochreous 138 HYMENOrTERA. hairs, becoriing shorter and black on the vertex. The nest, preserved in the Harris collection, now in the Mnsenm of the Boston Society of Natural Histor}^, is made of rose-leaves, and is scarcely distinguishable from that of M. centunc^daris. Osmia, the Mason Bee, is another genus of Carpenter or Upholsterer bees. The species are generally bluish, with greenish reflections, with smooth shiny bodies, and the species are of smaller size than in Megachile. The tongue in this genus is three times as long as the labium, tapering from the ))ase to the acute apex, and clothed with short hair. Mr. F. Smith states that the larva of the English species hatch in eight days after the eggs are laid, feeds ten to twelve days, when it becomes full-grown, then spins a thin silken covering, and remains in an inactive state until the following spring, when it completes its transformations. The habits of the little Mason-bees are quite varied. They construct their cells in the stems of plants and in rotten posts and trees, or, like Andrena, they burrow in sunny banks. An European species selects snail-shells for its nest, wherein it builds its earthen cells, while other species nidificate under stones. Curtis found two hundred and thirty cocoons of a British species {Osmia paretiva)^ placed on the under side of a flat stone, of which one-third were em})ty. Of the remainder, the most appeared between March and June, males appearing first ; thirty-flve more bees were develoi)ed the following spring. Thus there were three successive broods for three succeeding years, so that these bees lived three years before arriving at maturity. Mr. G. R. "\Taterhouse, in the Transactions of the Entomo- logical Society of London, for 1864 (3d series, vol. 2, p. 121), states that the cells of Osmia leiicomdana "are formed of mud, and each cell is built separately. The female bee, having de- posited a small pellet of mud in a sheltered spot between some tufts of grass, immediately commences to excavate a small cavity in its upper surface, semiring the mud away from the <-entre towards the margin by means of her jaws. A small shallow mud-cup is thus produced. It is rough and uneven on the outer surface, but beautifully smooth on the inner. Cu witnessing thus much of the work performed, 1 was struck with APIARI^. 139 three points. First, the rapidity with which the insect worked ; secondly, the tenacity with which slie kept her original position whilst excavating ; and thirdly, her constantly going over work which had apparently been completed, . . . The lid is excavated and rendered concave on its onter or upper surface, and is convex and rough on its inner surface ; and, in fact, is a simple rei)etition of the first-formed portion of the cell, a part of a hollow sphere." The largest species of Osmia known to us is a very dark-blue species Avhich seems to be undescribed. We will call it the wood-boring Osmia {Osmia Ikjnivora). It is larger than the Osmia lignaria of Say, being just half an inch long. The head is much shorter, and less square than in Say's spe- cies. The front of the head below the antenna? is clothed with dark hairs, but above and on the thorax with yellowish ochrcous hairs. The body is deep blackish blue, Avith greenish refiec- tions. We are indebted to a lady for specimens of the bees with their cells, which had been excavated in the interior of a maple tree several inches from the bark. The bee had industri- ously tunnelled out this elaborate burrow (Plate 4, Fig. 12), and, in this respect, resembles the habits of the Carpenter-bee {Xylocojxi) more closely than any other species of its genus. The tunnel was over three inches long, and about three- tenths of an inch wide. It contracted a little in width between the cell, showing that the bee worked intelligently, and wasted no more of her energies than was absolutely necessary. The burrow contained five cells, each half an inch long, being rather short and broad, with the hinder end rounded, while the opposite end, next to the one adjoining, is cut off" squarel}'. The cell is somewhat jug-shaped, owing to a slight constriction just behind the mouth. The material of which the cell is com- posed is stout, silken, parchment-like, and vQvy smooth within. The interstices between the cells are filled with rather coarse chippings made by the bee. The bee cut its way out of the cells in March, and lived for a month afterwards on a diet of honey and water. It eagerly lai)ped up the drops of water supi)lied by its keeper, to whom if soon grew accustomed, and whom it seemed to recognize. The female of Osmia liyuaria Say MS., according to Dr. HX) HYMENOrTERA. Harris' MS. notes, was found in tlie i)crfoct state in cocoons within earthen cells under stoues, April lith. The cell she con- structs is half an inch long, oval, cylindrical, and contracted slightly into a sort of neck just before the opening for the exit of the bee. From Mr. James Angus I have received the pellets of pollen, about the size of a pea, in Avhich it deposits its eggs ; the larvte were about one-third grown in August. This species is larger than Osmia shniUima of Smith, Avliile the male antenna? are much paler, being fuscous. The front of the head is covered with long dense yellow ochreous hairs. The vertex is not of so dark a green as in 0. simillima, and is covered with coarse punctures. The thorax is heavily clothed with yellow ochreous, thick hairs. The abdomen is yellowish, and much more hairy. The legs are stout, fuscous, Avitli yel- lowish hairs. Length, .35 inch. Our smallest and most abundant species is the little green Osmia simillima of Smith. It builds its little oval, somewhat (irn-shaped cells, against the roof of the large deserted galls of the oak-gall fly (Diplolepis confluentus), placing them, in this instance, eleven in number, in two irregular rows, from which the mature bees issue through a hole in the gall (Plate 4,* Fig. ■]4. From specimens communicated b}^ Mr. F. G. Sanborn). The earthen cells, containing the tough dense cocoons, Avere arranged irregularly so as to fit the concave vault of the larger gall, which was about two inches in diameter. On emerging fiom the cell the Osmia cuts out Avith its powerful jaws an ovate lid, nearly as large as one side of the cell. Both sexes may be found in April and Ma}^ in the floAvers of the Avillow *ExPLAXATiON OF PLATE 4.— Fig. 1, a cell of the Humble-bee; natural size, with the i)olleii mass upou the top. Fig. 2, end view of the same mass, .showing the three eggs laid in three divisions of the cavity. Fig. 3, Xylocopa Virf/imcn, the Car|)enter Bee. Fig. 4, the larva of Xylocnpa Virfjinicn; natural size. Fig. ii, the nest containing the cells of the same, with the partitions and pollen masses, on which the young larva is seen in the act of feeding; natural size. Fig. t!, young larva oi Anthrax sinuosa; side view. Fig. 7, pupa ol' Anthrax siruiosa, side view; natural size. Fig. 8, the Leaf-cutter Bee (M'ef/achile), on a rose leaf, in the act of cutting out a circular piece. Fig. !), cells of Megachile, in the elder; natural size. Fig. 10, larva of Cerntinn dupUi, the little green Upliolsterer Bee; enlarged. Fig. 11, cells of the same in the stem of the elder; natural size. Fig. 12, cells of Osmia Ugnivora, new species, the wood-devouring iSIason-bee, exca- vated in the maple; natural size. Fig. l.'j, cells of Onmia simi/limn, the common green Mason-ljee, built in the deserted gall of the Oak-gall Fly. Fig. 14, a single earthen cell of the same: natural size. Fig. 1.5, pollen mass, or bee-bread of Osmia lif/naria ; natural size. It is made up of distinct pellets of pollen, which are probably stuck together with saliva. Plate 4. ARCHITECTURE OF BEES. APIAP.I^. 141 and fruit trees which blossom later. The antennae are black, and the green body is covered Avith fine white hairs, becoming yellowish above. In the Harris collection are the cells and specimens of Osmia jxic{fica Say, the peaceful Osmia, which, according to the man- uscript notes of Dr. Harris, is found in the perfect state in earthen cells (Plate 5, Fig. 2) beneath stones. The cell is oval cylindrical, a little contracted as usual with those of all the spe- cies of the genus, thus forming an urn-shaped cell. It is half an inch long, and nearly three-tenths of an inch wide, while the cocoon, which is rather thin, is three-tenths of an inch long. The following genera, called Cuckoo Bees, are parasitic on other bees, laying their eggs in the cells, or nests, of their host. In Coelioxys the body is stout, and the bee closely mimics its host, Megaehile. The ligula is very long, being almost three times the length of the labium, and the paraglossae are wholly wanting ; the maxillar}' palpi are short, three-jointed, and the abdominal tip of the male is variously toothed. Coelioxys octo- dentata Say, is abundant late in the summer about flowers. An allied genus, 3felecta, is parasitic on Anthophora, and Epeolus is parasitic on Colletes. The species of Nomada are very numerous ; in all, the tongue is long and acute, with paraglossae about one-fourth as long as the tongue ; the maxillary pair of palpi are six-jointed ; and there are three subcostal cells. The species in their slen- der, smooth, gaily colored bod}^ resemble the wasps. These Cuckoo-bees lay their eggs in the nests of Andrena and Ha- lictus, and, according to English authors, Panurgus and Eucera, where they may be found in all stages of development corre- sponding to those of their hosts. The females do not sting severely. The species emit sweet, balmy, or balsamical odors. Shuckard states that these bees should be killed with burning suli)hur to preserve their bright colors. The larvie differ greatly from those of their hosts, Andrena, the head being much smaller, the body being smoother and rounder, and belonging to a more degraded, lower t3'pe. The whole body is more attenuated towards both extremities. The pupa differs from those of any other genus of this family known to us, except Andrena, by having three conspicuous 142 HYMENOPTERA. spines on tlie upper and posterior edge of the orbit, wliich are also fpiind in tlie pupa of Stignius, a Crabronid genus, and which evidently aid in locomotion. Thus the same law of degrada- tion obtains in these highly organized bee-parasites as in the lower parasitic species, though in a much less marked degree. From specimens found in the nests of Andrena and Halictus, collected at Salem by Mr. J. H. Emerton, and now in the Mu- seum of the Essex Institute, we have been enabled in great part to clear up the history of this bee. AVe have found in the nests of Andrena vicina both sexes of Nomada imhrkata Smith, and several females of Nomada indcheUa of Smith ; and in the cells of Halictus parallelus Say, specimens of Nomada imbri- cata. Both full-grown larv^ and pupte of different ages, up to the adult Nomada, ready to take leave of its host, were found in the cells of the Andrena vicina. It seems, there- fore, that the newl}- hatched young of Nomada must feed on the pollen mass destined for the Andrena. But there seems to be enough for both genera to feed upon, as the young of both host and parasite were found living harmoniously to- gether, and the hosts and their parasites are disclosed both at the same time. Does not this mild sort of parasitism in No- mada throw much light on the probable habits of Apathus, the Humble-bee parasite? It is more than probable that the Apa- thus larvre simply eat the food of the Bombus larvse, and do not attack the larvae of their hosts. Both Nomada and Apathus in their adult stages live harmoniously with their hosts, and are seen gathering food from the same flowers, and fl^^ing about the same nest. In the second subfamily, Andrenetce, the ligula, or tongue, is for the most part short and broad, and the maxillary palpi have four joints of equal size. In Sphecodes the body is smooth and wasp-like, and in its habit of running and flying in dry sandy places, it resembles Sphex, whence its generic name. The abdomen is generally light red, farther aiding in the resemblance to the Sphegidoc . The ligula is short, lancet-shaped, fringed with setae ; the para- glossie are not so long as the tongue, Avhile the labial palpi are shorter than the paraglossje, and the maxillae are broad, lan- ceolate, with six-jointed palpi. The antennae of the males are APIARI^. j^3 short and sometimes monillforra. Sphecodes clichroa Harris is our most common species. Mr. F. Smitli, from direct observa- tion, stcates tliat this genus builds cells, though earlier authors have stated that it is parasitic on Ilalictus and Andrena. Prosopis is generally yellow on the face, and is "less pulies- cent than any of the bees." The tongue is broad, subemar- ginate, the paragloss.-e reach a little beyond the tongue ; the labial palpi are as long as the tongue, while there are two sub- costal cells in the fore wings. Smith states that the genus is not parasitical as formerly supposed, as he has "repeatedly bred them" from cells laid in a regular order in the hollow of bramble stems. Mr. S. Saunders has also raised them in Alba- nia where "they construct their cells in bramble sticks (whicli they bore in the same manner as Colletes) with a thin transpa- rent membrane, calculated for holding semi-liquid honey, which they store up for their young. The species are much attacked by Stylops." Like Sphecodes and Ceratina, this genus, accord- ing to Smith, is unprovided with pollenigerous organs. We have several species in this country of which P. affinis Smith, and P. elliptica Kirby, are found northward. The habits of our species are not known. AiigocJdom comprises beautiful shining metallic green spe- cies, very commonly mot with. The thorax is globose, and the anterior wings have one marginal and three subniarginal cells ; the first submarginal cell as long as the second and third united. Augochlora paras Smith is a small, green, rather common species. Mr. J. II. Emerton has found its nests in Sa- lem, near those of Andrena. The "mouth of the hole opener! under a stone, and was built up so as to form a tube of saud (Plate 5, Fig. 1). The burrow on the 28th of June was four inches deep. Andrena is a genus of great extent, and the species are often difficult to distinguish. The lanceolate tongue is moderately long, and the paraglossia are half as long as the tongue itself, while the six-jointed maxillar}^ palpi are longer than the maxilhe themselves. The wings have three subcostal cells, with the rudiments of a fourth one ; the second is squarish, and the third receives a recurrent nervure near the middle. The pos- terior legs "have a long curled lock upon the trochanter be- 144 HYMENOPTERA. neath, and the anterior upper surface of the femora is clothed -with h>ng loose hair, which equally surrounds the whole of the tibijie." (Shuckard.) The abdomen is banded more or less conspicuously Avith reddish. The larva (Fig. 80) is stout and thick, with a head of moder- ate size, and the mouth -parts are a little shorter than usual, the maxillae and labium especially. The segments of the body are much more convex (angularly so) than usual, giving a tuberculate outline to the body. It is stouter than that of Halictus, the wings are less convex than in that genus ; while the maxillse are much stouter and blunter. The pupa is distinguished from the other genera by much the same characters as the imago, except that there Fig. 70. j^j.g ^^vo tubercles on the vertex near the ocelli. From a comparison of all its stages, this genus stands inter- jnediate between those placed above, and Halictus, which, in all its characters, is a more degraded form. The males often differ widely from the other sex, in their broad heads and widely spreading bidentate mandibles. Mr. Eraerton has observed the habits of our most common species, Andrena vlcina Smith, which builds its nest in grassy fields. The burrow is sunken perpendicularly, with short pas- sages leading to the cells, which are slightly inclined downwards and outwards from the main gallery. The Avails of the gallery are rough, but the cells are lined with a mucus-like secretion, which, on hardening, looks lilvc the glazing of earthen-ware. In Fig. 80 ]Mr. Emerton gives us a profile view of natural size of the nest showing the main burrow and the cells leading from it ; the oldest cell, containing the pui)a (a) is situated nearest the surface, while those containing larviis (b) lie between the pupa and the cell (e) containing the pollen mass and egg resting upon it. The most recent cell (/) is the deepest down, and contains a freshly deposited pollen mass. At c is the begin- ning of a cell ; g is the level of the ground. The bees were seen at work on the 4th of May, at Salem, Mass., digging their holes, one of which was already' six inches deep ; and by the loth, hundreds of holes were observed. On the 28th of May, in unearthing six holes, eight cells were found to contain pol- APIAEI^. 145 h JN len, and two of them a small larva. On the 29th of June six full-grown larvse were exhumed, and one about half-grown. About the first of August the larva transforms to a pupa, and during the last week of this month the mature bees appear. In Halictus, which is a genus of great extent, the head is trans- verse, and flatfish ; the mouth- parts are of moderate length, the tongue being very acute, with acute paraglossae half the length of the tongue, while the labial palpi are not quite so long as the paraglossiB. There are three subcostal cells in the wings, with the rudiments of a fourth often present, and the second cell is squarish. The abdomen is ob- long ovate, with a longitudinal linear furrow on the tip in the female. In the males the body is longer and the antennae more filiform and slender than usual in this family. The larvae are longer, and with more acutety convex segments than in Andrena. The pupae differ much as the adult bees from /'' Andrena, especially in the shorter mouth-parts. Halictus parallelus Say excavates cells almost exactly like those of Andrena ; but since the bee is smaller, the holes are smaller, though as deep. Mr. Emerton found one nest, in a path, a foot in depth. Another nest, discovered September 9th, was about six inches deep. The cells are in form like those of Andrena, and like tliem are glazed within. Tlie egg is rather slender and much curved ; in form it is long, cylindrical, ob- tuse at one end, and much smaller at the other. The larva 10 C FiK 80 146 HYMENOPTERA. Fiar. 81. (Figs. 79, 81) is longer and slenderer, and quite different from the rather broad and flattened larva of Andrena. The body is rather thick behind, but in front tapers slowly towards the head, which is of moderate size. Its body is somewhat tuberculated, the tubercles aid- ing the grub in moving about its cell. Its length is .40 of an inch. On the pupa are four quite dis- tinct conical tubercles forming a transverse line just in front of the ocelli ; and there are also two larger, longer tubercles, on the outer side of each of which an ocellus is situated. Figure 82 represents the pupa seen from beneath. Search was made for the nests on Jul}' 16tli, when the ground was very hard for six inclies in depth, below which the soil was soft and fine, and over twenty cells were dug out. "The upper cells contained nearly mature pupsie, and the lower ones larvne of various sizes, the smallest being hardly distinguishable by the naked eye. Each of these small larviB was in a cell by itself, and situated upon a lump of i)olleu, which Avas of the size and shape of a pea, and was found to lessen in size as the larva grew larger. These young were probably the offspring of several females, as four mature bees Avere found in the hole." (Emerton.) The larva of an English species hatches in ten daj's after the eggs are laid. Another brood of bees appeared the middle of September, as on the ninth of that month (18G4) Mr. Emerton found sev- eral holes of the same species of bee made in a hard gravel road near the turnpike. When opened, they Avere found to contain several bees with their 3'oung. September 2, 1867, the same kind of bee was found in holes, and just ready to leave the cell. Like Bombus, the females are supposed to hybernate, the males not appearing until late in the season. Like Andrena, these bees suffer from the attacks of Stylops, and according to Shuckard, an Ichneumon preys upon them, while certain spe- cies of Cerceris, Philanthus, and Crabro carry them off to store their nests Avith. VESPARI.E. 147 In CoIIetes the females, as Shuckard observes, resemble the workers of the Honey-bee, while there is considerable disparity between the sexes, the males being much smaller, the tongue and maxillae very short ; and the four-jointed labial palpi much shorter than the paraglossai. Tliere are three subcostal cells, with the rudiments of a fourth. These bees form large colo- nies, burrowing in the earth eight or ten inches deep, lining their cells "at the farther end with a very thin transparent mem- branaceous coating, resembling goldbeaters' skin." They thus furnish six or eight cartridge-like cells, covering each with a cap, "like the parchment on a drum-head." Smith, from Avhom we have been quoting, states that MiJtogramma jyunctata, which is a Tachina-like fly, and the Cuckoo-bee, Epeolus variegatus, have, in Europe, been reared from their cocoons. Vespari.e Latreille, Wasj^s. In this family, which comprises about 900 species, the body is more attenuated, more C3dindri- cal, with a harder and smoother tegument than in the ApiariK . In the species with densely populated colonies, such as Vespa and Polistes, there are workers which are often ver}^ numerous, while in Einnenes and Odynerus, etc., there are only males and females. The antenna? are elbowed, the mandibles are large, stout ; the maxilhe and labium of var3ing length ; the maxil- lary palpi are six-jointed ; while on the labial palpi, which are four-jointed, there are well-developed paraglossae. The pro- thorax is prolonged on each side to the insertion of the wings which are long and narrow, and once folded longitudinally when at rest ; the fore pair have two or three subcostal cells ; the hind shanks and til)iie are smooth. The eggs, when first laid, are globular, soon becoming oAal. The larvjie of this family are soft, fleshy, with larger heads in proportion to the rest of the body, than in the Apiarice; the antennal tubercle, or rudimentary antennae, are more dis- tinct, and the mandibles are larger. The surface of the body is smoother in Vespa and Polistes, l)ut more tuberculated in the solitary genera, Odynerus and allies, wliile the end of the body is more acute. As in the Apiarim the higher genera are social, building papery nests, while the lower are solitary and build cells of mud or sand in protected places. 148 HYMENOPTERA. In Vespa, the Paper Wasp, the ligula is squarish, with the paraglossai nearly as long as the tongue, the outer maxillary lobes rounded oval, half as long as the palpi, and the labial maxilhe are scarcely longer than the tongue. The abdomen is broad at base, acutely conical. The nests are either with or without a papery covering, supported by a short pedicel. Such females as have hybernated, begin to makfe their cells in the early part of summer. Smith states that the soli- tary female wasp " begins by making three saucer-shaped re- ceptacles, in each of which she deposits an egg ; she then proceeds to form other similar -shaped receptacles, until the eggs first deposited are hatched and the young grubs require a share of her attention. From the circular bases she now be- gins to raise her hexagonal cells, not building them up at once, but from time to time raising them as the young grubs grow. (Proc. Ent. Soc, London, 1858, p. 35.) Waterliouse states that the cells formed by the solitary fe- male early in the season appear " to be built entirely of glisten- ing, whitish, silk-like threads which I have little doubt are a secretion from the insect, all the threads being firmly attached together as if they had originally been of a glutinous nature." The cells formed later in the season by the workers, differ in consisting of masticated rotten wood. "Almost simultane- ously Avith the eomuiencement of the cells, it ai)pears that the nest-covering is cominonced. At first it has the appearance of a miniature umbrella, serving to shelter the rudimentary cells." I'late 5, Fig. 3, shows a group of cells surrounded by one layer of paper, and the beginning of another. As the nest grows larger the cells are ar- ranged in galleries, supported by pedicels, and the number of layers in the outside covering greatly increases in numl)er. While our common and largest species, Vesjxt, maculata Linn. (Fig. 83), and the j^ellow wasp, Fig- 83. Y, are»ar/« Fabr., build papery nests consisting of several galleries, with the mouth of the cells directed downwards, the East Indian species, V. oriantalis^ VESPARIJE. 149 builds its ceils of clay, and, according to Waterhouse, "tlie work is exceedingly beautiful and true." Another species, according to Smith, makes its nest of sandy loam, the exterior being so hard that a saw used in opening one of its sides was blunted. The larva of Vespa arenaria is long and cylindrical, not so much curved as in Polistes. Its position in its cell corre- sponds to its form, as the cell is longer and narrower than that of Polistes. Each segment of the body is posteriorly some- what thickened, as is the lateral (pleural) ridge of the body. The tip of the abdomen is rather blunt, the last sternite be- ing large and transverse. The pupa is provided with a single tubercle on the vertex, where there are two in the Crahron- idce and Sphegidm. By the time the nest of V. arenaria is large enough to contain ten full-grown larvge, and has about fourteen cells in all, being about an inch in diameter, the occupants of the two or three central cells will have changed to pupte, and one wasp will have been excluded. In a nest of the same species two inches in diameter, there were a second brood of larvae. The outer row of cells were occupied by pupae, while the central ones, emptied of the first brood, were filled with a second brood of larvre. Evidently as soon as an imago leaves its cell, the female deposits an egg therein, as very minute larvae were found occupj'ing cells next to those containing large full-grown larvae. In comparing a number of pupae from a large nest, they will be found to be in all stages of perfection, from the larva which has ceased feeding, and is preparing to transform, to the imago, still veiled by its thin subimago pellicle. It is dif- ficult to draw lines between these stages. Also when com- pared closely side by side, it is difficult, if not impossible to find any two pupae just alike, the development proceeding very un- equally. Thus the limbs may be more perfect than the antennae, or certain parts may be less perfect in some than in others, while the limbs may be more highly colored like the imago. Like the bees, Vespa suffers from numei'ous parasites, includ- ing Rhipiphorous paradoxus, which is a beetle allied to Stylops, and Lebia ^.Dromius) linearis. The larva of Volucella is said 150 HYMENOPTERA. to feed on the Vespa-larvie, and Mr. Stone says that Anthomyia incana is also parasitic in Wasps' nests, wliile two species of Ichnenmons, one of which is Anomalon vesparum, also in- fest the larvaj. No parasites have been as yet detected in this country. The Hornet, V. crabro Linn., has, according to Mr. Angus, become domesticated about New York. This and the smaller wasps are sometimes injurious b}' eating into ripe fruit, but the injury is more than counterblanced by the number of flies an(( other insects they feed their young with. Indeed, as Saussure states, the species of Vespa are more omnivorous in their tastes than any other wasps. They live by rapine and pillage, and have obtained a worse repute than other insects more injurious. In spring and early summer thej' feed on the sweets of flowers ; but later in the season attack straAvber- ries, plums, grapes; and other fruits, and often enter houses and there help themselves to the dishes on the table. They will eat raw meat, and then aid the butcher by devouring the flies that lay their eggs on his meats. The}' will sometimes destroy Honey- bees, attacking them on their return from the fields laden with pollen ; they throw themselves upon their luckless victims, and tear the abdomen from the rest of the body, and suck theii- blood, devouring only the abdomen. They fall upon flies and butterflies, and, biting otf their wings, feet, and head, devour the trunk. In attacking insects they use only their powerful jaws, and not the sting, diflfering in this respect from the fossorial wasps. Saussure states that though wasps do not generally la}- up food, yet at certain periods they do fill the cells with honey. The females feed their ^oung with food chewed up and re- duced to a pulp. Saussure questions whether the larviie of one sex are not fed on animal and the other on vegetable food, since Huber had shown "what a great influence the kind of food exerts on the sex of Bees." But it is now known that the sexes of some, and probably all insects are determined before the larvae is hatched. I have seen the rudiments of the ovi- positor in the half-grown larvse of the Humble-bee, and it is most probable that those rudiments began to develop duriiig embryonic life. It is far more probable that the sexual differ- ences are determined at the time of conception. VESPART.I!:. 151 Westwoocl states that the hxrv;ie, which live head-dowiiAvard from the reversed position of the coinb, retain their position in tile cell, while yonng, by a glutinous secretion, and afterwards "by the swollen front of the body which fills the open part of the cell." "Tlie female cells are mostly placed apart from those of the males and neuters, tliose of the males being often mixed, but in a small number, in the neuter combs. The egg state lasts eight days, the larva state thirteen or fourteen, and that of the pupa about ten. After the imago has been produced, one of the old workers cleans out the cell, and fits it for the reception of a fresh inhabitant. The upper tier of cells, being first built, serves for the habitation of the workers ; the females, being produced at the end of the summer, occupy the lowest tiers." When about to transform the larvae spin a thin cover- ing, thus closing over the cell. In PoUstes the paraglossia are slender, and a little longer than the long, or as in one instance noticed by us in P. Cana- densis, barrel-shaped ligula, which is split at the end ; the palpi are stouter, while the whole body is much longer than in Vespa ; the abdomen is subpedunculate, and the thorax is rather ob- long tlian spherical, as in Vespa. The larva ditfers from that of Vespa in its much larger head, and shorter, more ovoid form of the body, which is dilated in front so as to retain the insect in its cell, while the tip is more acute ; the antennal tubercles are closer together ; the clypeus is more regularly triangular and more distinct, while the labrum is much larger and excessivel}^ swollen, as are the mouth-parts generally. The mandibles are bidentate, where in Vespa they are tridentate. The pupa differs from that of Vespa, besides the usual generic characters, in having the tuberclg on the head smaller. The nests of Polistes (Plate 5, Fig. 4, nest of P. annularis Fabr., from Saussure) are not covered in by a j^apery wall as in \'espa, but ma}- be found attached to bushes, with the mouth of the cells pointed downwards. "While at Burksville Junction, Va., in the last week of April, I had an opportunity of watch- ing three species beginning their cells on the same clump of bushes. They all worked in the same method, and the cells only differed slightly in size. The cells Were formed mostly of 152 HYMENOrXERA. crude silk, and the threads could be seen crossing each other, the same stjucture being observed at the top and bottom of each cell. In the three-celled nest of Polistes (Plate 5, Fig. 5, 5 a) first noticed April 29th, there were but two eggs deposited, the third cell being without an egg, and a little smaller, and th3 rim not so high as in the other two. The outer edge did not seam to be perfectly circular, though stated by Water- house to be so in the incipient cells, for in some cases we de- tected two slight angles, thus making three sides, which, however, would be easily overlooked on casual observation ; as there are only two sides withhi, the cell, from being at its earliest inception hemispherical, or "■saucer-shaped," becomes five, and subsequently six-sided, and thus from being cir- cular, it is converted by the wasps into a hexagonal cell. In some cells, perhaps a majority, both in this and the other spe- cies, the newly made rim of the small cells is thinner than the parts below, and slightly bent inwards ; thus being quite the re- verse of the thickened rim of the cells of the Hive Bee. It would seem that the wasp plasters on more silk, especially' on the angles, building them out, and making them more promi- nent, in order to complete, when other cells are added, their hexagonal form. The three cells are of much the same size and height when the third egg is laid, as we observed in another nest, that of Polistes Canadensis (Linn.), built at the Defences of Washington, near Munson's Hill, June 9th. Again, when one or two more cells have been added to the nest, and there are four or five in all (Plate 5, Fig. 6 ; 6a, top A'iew, in which there are four cells), two of them are nearly twi^te as large as the others, while the fifth has been just begun, and is eggless. The form of the two which run up much higher than the others is the same as that of the smaller and shorter ones, i. e. they are on one side nearly semicircular, and on the other, partly hexagonal, and the angular sides shoAV a tendenc_y to be even more circular than when the others are built around them, for the little architect seems to bring out the angles more prominently when can-ying up the walls of the other cells. Thus she builds, as if by design, one and the same cell both by the "ciicular" and "hexagonal" methods, afterwards adopt- VESPARi^:. 153 ing only the latter, and if she dcAotes her attentions specially to plastering the corners alone, with the design of making the cell six-sided, then we must allow, contrary to Mr. Water- house's views, that the wasp builds the hexagon by choice, and not as the mere result of her blindly "working in segments of circles ;" for if our point be proved, and the most careful obser- vation of the wasp while at work is needed to prove it, then it may be shown that the wasp is a free agent, and can abandcju one method of working at a certain stage of her work, and adopt a different mode of operating. The eggs are oval, pointed at the end, and glued to the in- side of the cell. They are situated midwa}'^ from the top and bottom of the incipient cell, and placed on the innermost sides, so that in a group of several cells the eggs are close together, only separated by the thin cellular walls. In a completed cell the egg is placed very near the bottom. For several days a Polistes Canadensis was engaged in build- ing its nest in my tent in camp near Washington. When first noticed on June 9th, there were three cells, two of which con- tained eggs; and it was not for two da^s, the 11th, that the third cell was completed, and a third egg deposited in it. The wasp paid especial attention to strengthening the pedicel, going over it repeatedly for an hour or two with its tongue, as if lay- ing on more silken matter, and then proved the work l:>y its swiftly vibrating antennne. It would often fly out of the tent, and on its return anxiously examine each cell, thrusting its head deep down into each one. It gradually became accustomed to my presence, but eventually abandoned the nest, without adding more cells. The others, while at work on the bushes, abscond- ed at my approach, and seemed very wary and distrustful, as if disirous of concealing their abodes. Mr. Smith has found Trig niaJys hipusUdatus to be a parasite on Polistes lanio Fabr. {P. Canadensis Linn.), from St. Salvador, S. A. Saussnre arranges the higher Vespidre into two parallel series. Vespa is offset by Chartergus and Nectarina ; lower down we find Tatua and Synoeca, while Polistes is offset by Polybia. These five genera are tropical, and in their habits, the general appearance of their nests, and in the number of individuals represent Vespa and Polistes of the temperate zone. The 154 HYMEXOPTERA. genus Nectarina is a short plump wasp, somewhat like Odjne- rus ia shape ; its distinguishing mark is the concealment of the postscutellum by the scutelhnn. Nectarina melUjica Say, of Mexico, builds a large nest externally like that of a wasp, but it is more irregular, and the papery covering consists of but one layer. The interior of the nest is very difterent, the galleries of cells, instead of being parallel, being arranged in concentric spheres. Chartergus has the tip of the clypeus slighted excavated, and an oval sessile abdomen. C. chartarias Olivier makes an ex- ceedingly thick tough nest, attached by a broad base to the bough of a tree, about twice as long as thick, and ending in a cone, pierced in the centre by the entrance which passes through the middle to the basal gallery ; the other galleries are formed by a continuation of the sides of the nest, and arranged in a conical plane. In Tatua, the abdomen is pedicelled, but the petiole is not enlarged, and the abdomen itself is very regularly conical. T. morio Cuvier, from Cayenne, forms a nest like that of Charter- gus ; but the galleries form a flat floor, and each gallery has an entrance fro;n the outside of the nest, where in the latter there is one comuDu entrance. Plate 5, Fig. 9, shows how the bases of the cells are laid out on the edge of a galler}-. In SyiKieca the peculiarly shaped alxlomen is cordate and compressed. The curious nest of *S'. cyanea Fabr. is formed of a single layer of cells fixed against the trunk of a tree, and covered in with a dense covering made from the bark of dead trees. Some nests of Synoeca are three feet long. In the very extensive genus Poli/bia^ which resembles Polistes in its general shape, the abdo- men is pedicelled, and the mandibles are four-toothed. The nests are somewhat like those of Chartergus, but much smaller. Sev- eral species occur in Mexico, and in Brazil the number of si)ecies is very great. In Apoica the abdomen is very long, and the third segment is as long as the second. Plate 5, Fig. 1 1, represents the nest of Ajioica pallida Olivier, from Cayenne. It is unprotected, with a conical base, and with a single row of cells. In Icaria we have an approach to Polistes in the slender series of cells composing the nest, forming two or three rows ' VESPARI.E. 155 only. Plate 5, Fig. 7, represents the nest of I. gxittatipennis Saussure, from Senegal ; 8, ground plan of a similar nest. These wasps are mostly distinguished from Polybia hy the petiole ending in a globular mass. Plate 5, Fig. 10, represents the elegant nest of Mischocyttaras labiatus Fabr., from Caj-- enne and Brazil, which consists of a few cells supported by a long pedicel. The wasp itself much resembles Polistes, but the petiole is very much longer. The remaining genera noticed here are solitary, building separate cells, and with onl}' males and females. There are three subcostal cells in the fore wings, and the maxillai and labium are much elongated. In Eumenes the abdomen has a long pedicel, being sessile in Odynerus. While authors place P^umenes higher than Od}'- nerus, we would consider the latter as a higher, more ccpha- lized form, since the abdomen is less elongated, and the head is larger. In Odynerus the ligula is long, deeply forked at the slender extremity, while the slender paraglossai are shorter, ending in a two-toothed claw-like tip ; the maxilhe are slender, and the palpi have an elongated basal joint ; the clypeus is nearly circular, toothed on the front edge. The larva differs from those of the higher Vespa run , in its more elongated hend, the square clypeus, the unusually deep fissure of the bilobate la- brum, and in the larger tubercles of the body, as the larva is more active, turning and twisting in its cell, while feeding on its living food ; and in this respect it is more closely allied to the 3'oung Crahronido' . In the pupa of 0. aJbopIiaJeratvs^ tiie tip is more incurved than in the |)upa of Vespa, so that the hind legs (tarsi) reach to the tip, and the abdomen is rounded ovate, while in Vespa it is oblong. The cells (Plate 4, Figs. 13, 14) of Odynerus cdhnphcderatns Sauss. have been detected like those of Osmia in a deserted gall of Diplolepis confluens, where several were found in a row, arranged around one side of the gall, side by side, with the holes pointing towards the centre of the gall. The cells are half an inch long, and one-half as wide, being formed of small pellets of mud, giving a corrugated, granulated appearance to the outside, while the inside is lined with silk. 156 HYMEXOPTERA. We have received from Mr. Angus deserted cells of Cera- tiua in a syringa stem, in which we detected a pupa of an Odynerus, perhaps 0. leucomelas ; the cell was a little shorter than that of the Ceratina it had occupied. The cocoon of the Odynerus Avas of silk, and almost undistinguishable from the old cocoon of Ceratina. The wasp had dispensed with the necessity of making a mud cell. If future research shows that cither this or any other species makes a mud cell or not at will, it shows the intelligence of these little "free-agents;" and that a blind adherence to fixed mechanical laws does not obtain in these insects. Tiie larvjB of Odynerus and Eumenes are carnivorous. 1 found several cells of 0. albophaleratus, June 22d, in tlie deserted nest of a Clisiocampa^ which were stored with micro- lepidopterous larvai and pupa?, still alive, having been ])ara- lyzed by the sting of the wasp. The larvne of the wasp was short and thick, being, when contracted, not more than twice as long as broad ; the rings of the body are moderately convex, and the pleural region is faintly marked. Prof. A. E. Verrill has discovered the cells of an Odynerus at New Haven, forming a sandy mass (Plate 5, Fig. 12) attached to the stem of a plant. In Eumenes the lingua is very long, being narrower and more deeply divided than in Odynerus ; the second subcostal space of the wings is long and narrow, while in Odynerus it is triangular. The genus is easil}' recognized by the very long pedicel of the abdomen. Eumenes fraterna Say constructs a thin cell (Plate 5,* Fig. 15) of pellets of mud, and as large * EXPLANATIOX OF PLATE 5. Fig- 1- Mouth of the tunnel of Aiigorlilorn pnrus ; from Emerton. Fig. 2. Cells of O^mla pncificn ; coninnmic;ited by Mr, Sanborn. Fig. 3. Vertical section of nest of Vespa with a grou)) of primitive cells surrounded by one layer of paper, and part of another; from Saussure. Fig. 4. Nest of Po- Ustes aunidnrin • from Saussure. Fig. 5. Three primitive cells of Polistes; na, top view of the same, one being eggless. The sides adjoining are angular. Figs. (J and 6(7, a coll farther advanced, consisting of iour cells, each containing an c^g, and with the edges of the colls built up higher and more decidedly six-sided; original. Fig. 7. Cells of /cflj-ja gnttatipennis, showing that each cell is l)uiltup independently in regular hexagons. Fig. S. Ground plan of a similar nest. Fig. 9. Ground plan of cells of Tdtua morio ; from Smith. Fig. 10. Nest of Mischocyttnnt>< hihiatus : from Saussure. Fig. 11. Nest of Apu'icn pallida; from Saussure. Fig. 12 Nest of Odynerus birenimnculatus. Fig. 1.3. Nest of Odi/nerua alhophaleratns ; origiu&I, Fig. 14. Mud cell of Pelopmus Jtuvipea ; original. Fig. Li. A row of spherical cell» of E 11171671 es fraterna, with the female; from Harris. Plate ARCHITECTURE OF WASPS. CRABRONID^. I57 as a cheny. It is attached by a short stout pedicel to bushes, and the cavity is tilled with the larvtB of small moths. Rophiglossa oclyneroides, from Epirus, described by S. S. Saunders, makes elongated cells in galleries in briars, storino- them with the larvtie of what he supposed to be weevils. The dark brown dense tough cocoon of a Chrysis was also found in the cells. In J/«s«/vs, which connects the Vesjyar ice with the succeed- ing family, the wings are not completely folded when at rest ; there are but two subcostal cells ; the maxilhie are rudimen- tary ; and the antennae are clavate and eight-jointed. 3Iasaris vespokles Cresson, inhabits Colorado Territory. Crabkonid^ Latreille. Sand-imsps^ Wood-ioasps. In the more typical genera the head is remarkably large, cuboidal, while the clyi)eus is veiy short, and coveree Leach. Mr. F. Smith defines this fomily as having '•mandibles notched exteriorly near the base ; the labrum con- LARRID.E. 16.J C3aled, with a single spine at the apex of the intermediate tibiae ; the abdomen is ovoid-conieal." The genus Astata is a large hair}' form, with long antennjt and palpi and an elongated prothorax. Its spiny legs show its neiir rehitionship to the Sphegidce. Astata unicolor Say repre- sents the genus in this country. Tachytes is also of larger size than the following genus. It is covered with long dense golden short hairs, with a trap- ezoidal front. Tachytes aunilentus Fabr. is rare ; it frequents the flowers of the Asclepias, as we have found pollen masses at- tac'.ied to the spines of its legs. We figure (89) a tarsus of a wasp belonging probably to this genus, received from Mr. V. T. Chambers, showing the pollen masses of Asclepias at- tached to the spines. The genus Xarrar^a "contains those species which have the marginal cell truncated at the apex and appendiculated, and three submarginal cells, the first as long as the two following ; .• . . . the metathorax [])ropodeum] truncated posteriorly, elongate, the sides being generally parallel ; the mandibles are large and arcuate, with a tooth on their exterior towards the base ; abdomen ovate-conical, acuminate at the apex." Larrada, argentata Beauv. is covered with silvery pile. It is a slender form, with short, nearly unarmed legs. A Brazilian species of Larrada^ according to Mr. H. W. Bates, builds a nest composed apparently of the scrapings of the woolly texture of plants ; it is attached to a leaf, having a close resemblance to a piece of German tinder, or a piece of sponge. The cocoons were dark brown, and of a brittle consist- ency. The reporter, Mr. F, Smith, adds : "I am not aware of any similar habit of building an external nest having been pre- viously recorded ; our British species of the closely allied genus Tachytes, are burrowers in the ground, particularly in sandy situations; their anterior tarsi are strongly ciliated, the claws bifid and admirably adapted for burrowing. On examin- ing the insect which constructed the nest now exhibited, I find the legs differently armed ; the anterior pair are not ciliated, 166 HYMENOPTERA. and the claws are simple and slender, clearly indicative of a peculiar habit differing from its congeners, and how admirably is this illustrated in the nest before us?" Sphegid^ Latreille. Smith defines this family as having "the posterior margin of the prothorax not prolonged back- wards to the insertion of the wings, and anteriorly produced into a neck, with the abdomen petiolated." The very fossorial legs are long and spiny, the posterior pair being of unusual length. The mandibles are large, curved, narrow, and acute, the base not being toothed externally, and the antenna are long and filiform. The species are often gaily colored, being ornamented with black and red, brown and red, or are entirely black, or blue. They love the sunshine, are very active, rest- less in their movements, and have a powerful sting. The sting of these and other wasps which store up insects for their young, penetrates the nervous centres and paralj'zes the victim without depriving it of life, so that it lives many days. A store of living food is thus laid up for the young wasp. After being stung the caterpillars will transform into chrys- alids, though too Aveak to change to moths. Mr. Gueinzius, who resides in South Africa, observes that "large spiders and caterpillars became immediately motionless on being stung, and I cannot helj) thinking that the poisonous acid of Ilymen- optera has an antiseptic and preserving property ; for cater- pillars and locusts retain their colors weeks after being stung, ar,d this, too, in a moist situation under a burning sun." These insects either make their nests in the sand, or, like the succeeding family, are "mud-daubers," building their cells of mud and plastering them on walls, etc. The tropical genus Ampidex is more closely allied to the preceding family than the other genera. The species are brassy green. Dr. G. A. Perkins has described in the Ameri- can Naturalist, vol. 1, p. 293, the habits of a wasp, probably the Ampidex Sihirica Fabr., which inhabits Sierra Leone, and oviposits in the body of the cockroach. The dead bodies of the cockroaches are often found with the empty cocoon of tlie wasp occupying the cavit}^ of the abdomen. A species of this genus, abundant at Zanzibar at certain sea- SPHEGID.E. 167 sons, was frequently observed by Mr. C. Cooke to attack the cockroach. The cockroach, as if cowed at its presence, im- mediately yields without a struggle. The Ampulex stings and paralyses its victim, and then flies away with it. Chlorion is closely allied, containing blue and metallic green species, often with golden yellow wings. Chlorion cyaneum Dahlb., a blue species, is found in the Southern States. The genus Priononyx "differs from the genus Sphex in hav- ing the claAvs quadridentate beneath at their base ; the neura- tion of the wings and the form of the abdomen are the same as in Haiyactopus" which is found only in the tropics and Aus- tralia. Priononyx Thom(je is found from South Carolina to Brazil, including the West Indies. The genus Sj^hex is quite an extensive one. The head is as wide as the thorax ; the antennse are filiform, mandibles large and acute, bidentate within, the teeth notched at their base, forming a rudimentary tooth, the apical tooth being acute. The thorax is elongate-ovate, truncated behind, with a trans- verse collar (prothorax). The fore wings have one marginal and three submarginal cells ; the marginal cell elongate, rounded at its apex ; the first submarginal cell as long as the two following. The abdomen is pedun- culated, conically ovate, and the an- terior tarsi are cili- ated in the females. Sphex ichneumo- nea Linn. (Figure 90) is a large rust- red species, with a dense golden pu- rig. 90. bescence. It is common from Massachusetts southwards. In the last week of July, and during August and early in Sep- tember, we noticed nearly a dozen of these wasps busily en- gaged in digging their holes in a gravelly walk. In previous seasons the}' were more numerous, burrowing into grassy 1G8 IIYMEXOPTERA. banks near the walk. The holes Avere fonr to six inches deep. In beginning its hole the wasp dragged away with its teeth a stone one half as large as itself to a distance of eight inches from the hole, wiiile it pushed away others with its head. In beginning its burrow it used its large and powerful jaws almost entirely, digging to the depth of an inch in five minutes, com- pleting its hole in about half an hour. After having inserted its head into the hole, where it loosened the earth with its jaws and threw it out of the hole with its jaws and fore legs, it would retreat backwards and push the dirt still farther back from the mouth of the cell with its hind legs. In cases where the farther progress of the work was stopped by a stone too large for the wasp to remove or dig around, it would abandon it and begin a new hole. Just as soon as it reached the required depth the wasp flew a few feet to the adjoining bank and falling upon an Orchelimum vulgare or O. gi'acile, stung and paralyzed it instantly, bore it to its nest, and was out of sight for a moment, and while in the bottom of its hole must have deposited its egg in its victim. Eeappearing it be- gan to draw the sand back into the hole, scratching it in quite briskly by means of its spin}^ fore tarsi, while standing on its two hind pairs of legs. It thus threw in half an inch of dirt upon the grasshopper and then flew off". In this way one Sphex Avill make two or three such holes in an afternoon. The walk was hard and composed of a coarse sea-gravel, and the rapidity with which the Avasp worked her wa}' in with tooth and nail was marvellous. Sphex tibialis St. Fargeau is a black, stout, thick insect. Mr. J. Angus has reared this species, sending me the larva? in a cavity previously tunnelled by Xylocopa Virginica in a pine board. The hole was six inches long, and the oval cylin- drical cocoons were packed loosely, either side by side, where there was room, or one a little in advance of the other. The interstices between them were filled with bits of rope, which had perhaps been bitten iip into pieces by the wasp itself; while the end of the cell was filled for a distance of two inches with a coarse sedge arranged in layers, as if rammed in like gun-wad- ding. The cocoons are eighty to ninety hundredths of an inch long, oval lanceolate, somewhat like those of Pompilus. They SPIIEGID.E. 1G9 consist of two layers, the outer very thin, the inner tough, parchment-like. The larvic hybernate and turn to pupjie in the spring, appearing in the summer and also in the autumn. The larva is cylindrical, with tlie pleural ridge prominent, and with no traces of feet ; the head, which is small and not prominent, and rather narrow compared with that of Pelopsieus, is bent inwards on the breast so that the mouth reaches to the sternum of the fourth abdominal ring. The posterior half of each ring is much thickened, giving a crenulated outline to the tergum. The abdominal tip is obtuse. Sphex Lanierii Guerin, according to Smith (Proceedings of the Entomological Society of London, Feb. 7, 1859), con- structs its nest of a cottony substance, filling a tunnel formed by a large curved leaf. The species of the genus are sup- posed to burrow in the ground, and the two cases above cited show an interesting divergence from this habit. Mi'. Smith adds, that in "the Sphex which constructs the nest in the rolled leaf, the anterior tarsi are found to be veiy slightly ciliated, and the tibiie almost destitute of spines, thus afl'ording another instance proving that difference of structure is indica- tive of difference of habit." The genus Pelopanis is of a slighter form than in Sphex, the body being longer and slenderer ; the cl^peus is as broad as long, triangular above, in front convex, or produced and end- ing in two teeth. The outer costal cell is lanceolate oval, the second subcostal cell subtrapezoidal, being widest above ; it is also somewhat longer than broad. The first median cell is very long and narrow, much more so than usual. The pedicel of the abdomen is long, the first joint in the male being often as long as the remainder of the abdomen. The larva of P. ccendeus Linn, is much like that of Sphex, having a cylindrical body with the rings thickened posteriorly. It differs from that of Pomiiilus in its longer and narrower head, the short broadly trnpezoidal clypeus, and the distinctly marked exserted labrum. The mandibles are long and tridentate. The pupa (of P. flavipes) differs from that of the Vesparice in having the head more raised from the breast ; the palpi are not partially' concealed, as the}'^ may be easily seen for their whole length. The long curved mandibles cover the base of the 170 HYMEXOPTEIIA. maxilliE and lingua, and the antennje reach to the posterior coxae. The maxilhTe are slender, not reaching to the tip of the labium. The female usually provisions her cells (Plate 5, Fig. 14) with spiders. The cells are constructed of layers of mud of unequal length, and formed of little pellets placed in two rows, and di- verging from the middle. They are a little over an inch long, and from a half to three-quarters of an inch wide, and are some- what three-sided, the inner side next the object, either stone- walls or rafters, to which it is attached, being flat. As the earthen cells sufficiently protect the delicate larvae within, the cocoons are very thin, and brown in color. The cells of Pelopanis flavipes from BroAvnville, Texas, col- lected by an United States officer and presented to the Boston Society of Natural History, contained both spiders and numer- ous pup;e of a fly, Sarcophaga midipiennis Loew (MS) which is somewhat allied to Tachina. These last hatched out in mid- summer a few days before the specimens of Pelopaeus. It is most probable that they were parasitic on the latter. These specimens of P. flavipes were more highly ornamented with yel- low than in those found northwards in the Atlantic States, the metathorax being crossed b}' a broad yellow band. The genus Ammophila is a long slender form, with a petio- late abdomen, the tip of Mhich is often red. The petiole of the abdomen is two-jointed, and very long and slender, being longer than the fusiform part. In the males the petiole is in some species much shorter. The wings are small, with the apex more obtuse than usual ; the second subcostal cell is pentag- onal, and the third is broadly triangular, Westwood states that "the species inhabit sandy districts, in which A. sahulosa forms its burrow, using its jaws in bur- rowing ; and when they are loaded, it ascends backwards to the mouth, turns quickly around, flies to about a foot's distance, gives a sudden turn, throwing the sand in a complete shower to about six inches' distance, and again alights at the mouth of its burrow." "Latreille states that this species provisions its cells with caterpillars, but Mr. Shuckard states that he has observed the female dragging a YQvy large inflated spider up the nearly per- pendicular side of a sand-bank, at least twenty feet high, and POMriLlD^. 171 that whilst burrowing it makes a lond whirring buzz ; and, in the Transactions of the Entomological Society of London, lie states that he has detected both A. sabulosa and A. hirsnta dragging along large spiders. Mr. Curtis observed it bury the caterpillars of a Noctua and Geometra. St. P^argeau, how- ever, states that A. sabulosa collects caterpillars of large size, especially those of Noctnse, with h, surprising perseverance, whereas A. arenaria, forming a distinct section in the genus, collects spiders." (Westwood.) Ammophila cementaria Smith, and A. urnaria King, are the more common species in this country ; they are red and white, while A. luctuosa Smith is a black, shorter, stouter, more hirsute species. They may all be seen flying about hot sandy places, and aligliting near wells and standing water to drink. PoMPiLiD.E Leach. In this famil}' the body is oblong, the sides often compressed, and the head shorter, when seen from above, being more trans- versely ovate than in the preceding family. The antennoe are long, not geniculate, and in the males are stouter and with shorter joints than in the females. The eyes are narrow oval, and the maxillary palpi are six, and the hibial palpi four-jointed. The prothorax is ex- tended on the sides back to the base of the wings, ^'s- ^^• wiiich latter are large and broad, the fore pair having three subcostal cells. The legs are very long and slender, with thick slender spines. The Pompilidoi, of which about seven hun- dred species are known, have a wide geographical range, from the temperate zone to the tropics. Like the Sphegidcje, they oviposit in the body of other insects, storing their nests, usually built in the sand, with spiders and caterpillars. The head of Pompllus (Fig. 91) is a little longer, seen from 172 HYMENOPTERA. above, than in the other genera ; the front of the head is about a third longer than broad. The antennjie are long and fili- form and sometimes crenulate, as in Figure 91a, in the males ; the mandibles are stout, broad, sabre-shaped, being much curved, with low llattened teeth, and the maxillary palpi are longer than the labial palpi. The wings are rather broad, with the three subcostal cells Ij'ing in a straight row. The abdomen is slightly com- pressed, and equals in length the remainder of the body. The sting is very large and formidable, and ex- cessively painful, benumbing the parts it enters. They are exceedingly active, running and flying over sandy places like winged spiders. There are about five hundred species of this genus described.- They are usually shining black or deep bluish black, with Fig. ill rt. Fig. 92. smoky or reddish wings, and sometimes a reddish abdominal band. This genus is interesting, as affording in its form a mean between the globular thorax and short body of the ApiarifB and the elongated body of the Ichneumonidce. The Pompilus formosus Say (Fig. 92), called in Texas the Tarantula-killer, attacks that innnense spider the Myr/ale Hciitzii, and, according to Dr. G. Lincecum (American Naturalist, May, rO-MPILID.E. 173 18G7), paralyzes it with its formidable sting, and inserting an egg in its body, places it in its nest, dug to the depth ol" five inches. There is but a single brood, produced in June, which is killed off by the frosts of November. This species feeds in summer ''upon the honey and pollen of the flowers of the Polder, and of Vitis ampelopsis^ the Virginia Creeper ; but its favorite nourishment is taken from the blossoms of Asdepias quadrifolmm." (Lincecum.) P. cylindricus Cresson (Fig. 93, wing) is one of our smallest species, being IVom three to five lines long. It occurs in the South and West. P. arctus Cresson (Fig. 94, wang) in- habits Colorado Territory. J\ Clarice Cresson (Fig. 95, ? enlarged) is a beautiful and rare species found in Pennsylvania. The genus Priocneviis is characterized J)y the two hind pair of tibiiE being serrated ( 5 , Fig. 96, o, wing; b, pos- terior leg ; c, anterior leg), and by the want of spines on the an- terior legs. P. unifasciatus Say is a wide-spread species and readily recognized by the deep black color of the body, the 3'ellow an- tennae and the large yellow spot at the tip of each anterior wing. The genus Agenia (Fig. 97, o, wing ; b, posterior leg) differs in having smooth legs. A. brevis Cres- Fig. 96. son (Fig. 98, wing) is a little spe- cies found in Georgia. A. comjruus Cresson (Fig. 99, wing) was captured in West Virginia ; and A. acceptus Cresson (Fig. 100, wing) in Georgia. The genus Notocyplms (Fig. 101, ?, wing) is found in Brazil and Msxico. Planiceps (Fig. 102, Tig. 95. 174 HYMEXOPTERA. Wing) contains a few species, of which P. niger Cresson, an entirely black species, is found in Connecticut. Aporus (Fig. 103, wing) contains a single American species, A. fasciatus Smith, taken in North Carolina. From Mr. F. G. Sanborn we have re- ceived the larva and cocoon of Pompilus Fig. 97. fanereus St. Farg., a small black spe- cies, which builds its nest in fields. The larva is short and broad, with the lateral region rather prominent, and the tip of the abdomen rather acute. It differs from Pelopoeus in its stouter, rather flat- tened body, and thickened segments, though as our specimen is preserved in alcohol these characters may have be- come exaggerated. It more nearly re- sembles PelopjBus in its transverse clypeus, thin bilobate labrum, and the stout mandibles, which are, however, much stouter than in Pelopffius, while the whole head is shorter, broader, and rounder. It is probable that this pecu- liar form of the head (which as in Sphex is bent beneath the breast), together n-. i03. with the broad transverse clypeus, and broad, short, bilobate, thin, transparent labrum, and especially the unidentate short broad mandibles are family characters, sep- arating the larvae of this group from those of the Sphegidoz . The cocoon is ovate, long, and slender, much smaller at one end than the other, not being so regularly fusiform as in Sphex. Ceropales differs from the foregoing gen- rig. 100. Qj.^ ji^ itg broad head, its much shorter ab- domen ; and also in the eyes being a little excavated, in the depressed labium, the narrow front, Avhich dilates above and below the middle, and in the greatly elongated hind legs, gen- erally banded with red or whitish. Ceropales bi'pnnctata Say is generally distributed throughout the United States. It SCOLIAD.F.. 175 is easily recognized b}' tlie black body and legs, and red pos- terior femora, and is six lines long. C. Rohinsonii Cresson (Fig. 104, J ) is an elegant epecies found in West Virginia. An allied genus is Mycjniynia (Fig. 105, wing) containing M. 3[ex- icana Cresson and M. ns- tidataDahlh., two Mexican species. In the genus Pepsis (Fig. lOG, wing) the max- illary and labial palpi are of equal length. The spe- cies are large, some of them being among the lar- gest of riymenoptera, and are generully indigo-blue in color. Pepsis Jieros Dahlbom is found in Cuba; it is two inches long. P. cyanea Linn., wliicli is blackish-blue, witli blue abdomen and wings, the latter reddish at the apex, has been described by Beauvois from the United States, while P. elegcms St. Fai'g. also occurs in the Southern States. P. formosa Say affords another example of a species Fig. lOG. common to both sides of the Rocky Mountains, as it has been found both in Texas and Cal- ifornia. It is black, with bluish or greenish reflections, with bright fiery red wings, and is thirteen to eighteen lines long. ScoLiAD^ Leach. This family forms a group very easily distinguished from the Bemhecidce or Chrysidiclce , as well as the Pomp iUd(je, by the broad front, the small indented eyes, and the great sexual differences in the antennae, those of the male being long and slowly thickened towards the tip, while in 176 H Y M E XOPTE R A . the female they are short, thick, and elbowed on the second joint. The clypeus is large, irregularl}^ quadrilateral, becom- ing shorter in the lower genera, and the labrum is small, scarcely exserted, while the mandibles are, in the female es- pecially, large and broad. The prothorax is ver}^ square in front. In the fore-wings are three subcostal spaces. The abdomen in the typical genus (Seolia) is broad and flat, longer than the rest of the body. The abdomen of Mutilla approaches that of the Chrysididce in having the second ring much en- larged over the others. The males usually have the anal stylets very prominent, while the sting of the female is very powerful. The body and legs are generally very hirsute, and the first tarsal joint is as long as the tibiiie. The genus Sapyga is easily recognized by its smooth slender body, being ornamented with yellow, with transverse bands on the abdomen. The head is long, very convex in front, and the antenniB are clavate ; the prothorax is very broad, giving an oblong appearance to the thorax. The legs are slender and smooth. It is said to be parasitic, laying its eggs in the cells of Osmia. Sapyga Martinii of Smith is found northward. The species of Seolia are often of great size, being black and very hirsute, with the labium composed of three linear di- visions ; the abdomen alone being banded or spotted with yellow on the sides. They are found in the hottest places al)out strongly scented flowers. In Europe, Seolia hieineta ''makes its burrows in sand-banks, to the depth of sixteen inches, with a very wide mouth ; " and it is probable that the nest is stored with grasshoppers. Seolia quaclrirnaeulata Fabr. is found in the Middle and Southern States, The larva of Seolia flavifrons was found by I'asserini to live in the body of the lamellicorn beetle, Oryctes nasicornis. In Madagascar, Seolia oryetopliaga lives on Oryctes simia, according to Coquerel. Professor Sumichrast states that at Tehuacan (Department of Puebla) the Seolia Azteca Sauss. is ver^^ common ; and is particularly abundant in the leather tanneries, which leads him t) think that the females of this species also deposit their eggs under the epidermis of the larva which abounds in the tan. Tlpliia is black throughout and rather hirsute. The antenn.ie MUTILLAIIIJi:. 177 are shorter than in Scolia or Myzine ; the olypeus is also shorter, while the prothorax is longer. In the fore-wings the ouier cos- tal cell is short, broad, angnlated, OA'al ; and of the two sub- costal cells, the outer one is broad and triangular, twice as long as broad, while the first median cell is regularly short rhom- boidal, much more so than in the other genera. The females, according to Westwood, "make perpendicular burrows in sandy situations, for the reception of their eggs ; but the precise food stored up for the larvae has not been ob- served." Tiphia inornata Say is a common species with us, and flies low over sandy places early in the season. The short oval head, the large ej'es, short meso-scutum, large meso-scutellum, and the flattened, rather smooth body, characterize the geiuis Myzine. The females are very different from the males, the two sexes being for a long time considered as separate genera. The female, especiall}^, ditfers in the great length of the square prothorax, which is very broad and convex in front. In the male the eyes are lunate, while in the female they are small, entire, and remote. In its general form the fe- males much resemble Scolia, while the males are long and nar- row, with broad yellow bands, especially on the abdomen, and a large exserted fjting-like organ. Myzine sexcincta Fabr. is seen from New England southwards, flying low over hot sandy places. The genus EHs is closely allied. Sumichrast (American Nat- uralist, vol. 2), surmises that EJis costalis St. Farg. lives on certain Scaral)a.'ides, which undergo their metamorphosis in the formicary of Qicodoma in Mexico. MuTiLLARi^ Latreille. This interesting family is character- ized by the females alone being wingless, though Morawitz says that wingless males occur in two species ; and by the absence, generally, of the three ocelli. In Mutilla and Myrmosa the thorax is still high, compressed, and oblong cuboidal, and ex- cept in the closely united tergal pieces the females do not greatly recede from the t^'pe of the Avinged males. The species are very equal in size, are black, or black and red, and either smooth or hirsute. The antenujie are inserted low down on the front, the clypeus being very short and broadl}^ ovate (especially in M^-rmosa), 12 178 HYMENOPTERA. or it is indented, as in Mutilla, Tlie tongue is shorter than usual. The sides of tiie thorax contract in width, both before and be- hind. The ineso-scutura is sqnarer tlian usual, while the nieso- scutellum is much narrower and longer, and the propodeum is squarely truncated behind, thus presenting a full convex surface. The abdomen is not much longer than the rest of the body, be- ing shorter than usual. In all these characters this family shows its afTuiities to the Ants. The wings are very dissimilar in the difi'erent genera. In Myrmosa the neuration closely approaches that of Sapyga, while in the larger, more acute primaries of Mutilla, and especially in the short outer costal cell, and short open pterostigma, the latter genus differs from the others. The male of Scleroderma closely mimics the Procto- trypidai, the vehis of the wings being absent, Avhile the form of the head and abdomen also reminds us of some genera in that family. The wingless female is very diiierent, having more of the form of Mutilla, with a large oblong head and long acutely conical abdomen. The species are minute and rarely met with. S. contn'acta Westwood is found in "•Carolina." In the female Mcthoca the e^-es are ver}' long, and the seg- ments of the abdomen are Avidely separated, nuich as in the ants. 3Iethoca Canademns Smith is shin- ing black, and slightly villose. The species of Mi/nnosa may be known by the very short clypeus, the broad ver- tex, and the rings of the abdomen of the male being uiuisually contracted. The ri?. 107. abdomen of the female is cylindrical, about twice as long as broad, and thickest on the second ring. The rings are densely hirsute on the hinder edge. Myrmosa unicolor Say (Figs. 107, male ; 108, female) is widely distributed. We i have taken this species in Maine, while sex- | ually united, early in June. The wingless female is like an ant, and is pale reddish on the thorax and basal ring of the abdomen, and the antennae and feet are concolorous, while the head and remaining abdominal rings are much darker. It is .20 inch long. The male is .28 inch long and entirely black. FOiaiiCAiii^. 179 The genus 3IutiUa is a very extensive one, and enjoys a wide geographical range. It is throughout stouter than Myrmosa, the head is more cubical, and the thorax and abdomen is shorter, the tip of the latter being somewhat truncated. Th« wingless female closelj^ resembles, both in its form and motions, a worker ant. The body is coarsely granulated and either naked or densely hirsute, and of a scarlet, black, or pale red, or brown-black color. The females are found running in hot sandy places, and hide themselves quickly when disturbed, while the males frequent flowers. MutiUa occidentalis is a large species. It is of a beautiful scarlet color and is armed with a very powerful sting. According to Profes- sor A. E. Verrill this species was found by him, at ]Vew Haven, to construct deep holes in a hard beaten path, storing its nest with insects. This species is also said by Fi-. 109. Kirby to be very active, "taking flies by surprise." (West- wood.) Mr. Verrill noticed that this insect makes a slight creaking noise. The larvae of M. Europiaa are said to live parasitically in Humble-bees' nests. 3IutUla ferrugata Fabr. (Fig. 109) is found frequently in New England. FoRMiCARi^ Latreille. The family of ants would seem naturally to belong with the trul}' fossorial Ilymenoptera, both from their habits and structure. Both males and females are winged, but the males are much smaller than the females, Avhile the wingless Avorkers are smaller than the males. In these wingless forms the segments of the thorax become more or less separated, making the body much longer and slenderer, and less compact than in the winged nor- mal sexual forms, the prothorax being more developed than in the males and females. The workers often consist of two forms : one with a large cubical head, or worker major, some- times called a soldier, and the usual small-headed form, or worker minor. The head is generally triangular. The e^-es are large in the males, smaller in the workers, and in those of some genera (Ponera, Typhlopone, etc.) they are absent ; while in the 180 HYMENOPTERA. workers the ocelli are often wanting, though present in the winged individuals of both sexes. The antennaj are long, slender and elbowed. The mandibles are stout, and toothed, though in those species that do not themselves labor, but en- slave the workers of other species, they are uuarmed and slender. The maxillary palpi are from one to six-jointed, and the labial palpi two to four-jointed. The fore-wings usually have but a single complete subcostal (cubital) cell. The sling is often present, showing that in this respect as well as their fossorial habits the ants are triilj^ aculeate Ilymenoptera. The larva is short, cylindrical, Avith the end of the body obtuse. Tlie rings of the body are moderately convex. The head is rather small and bent upon the breast. The larvoe are fed by the workers with food elaborated in their stomachs. The larvffi of the stingless genera usually spin a delicate silken cocoon, while those of the aculeate genera do not. Both Latreille and "Westwood, however, state that sometimes, as in Formica fusca, of Europe, the pupce arc naked, and at other times enclosed in a cocoon. The colonies of the different species vary greatly in size. In the nests of Formica sanguinea the number of individuals is very great. The history of a formicarium, or ant's nest is as follows : The workers only (but sometimes the Avinged ants) hibernate, and are found early in spring, taking care of the eggs and larvae produced by the autumnal brood of females. In the course of the summer the adult forms are developed, swarming on a hot sultry daj'. The little jellow ants, abundant in paths and about houses in New England, generally swarm on the af- ternoon of some hot day in the first week of September, when the air is filled towards sunset Avith myriads of them. The females, after their marriage flight in the air, may then be seen cuternig the ground to lay their eggs for ncAV colonies, or, as A\''estwood states, they are often seized by the workers and retained in the old colonies. Having no more use for their Avings they pluck them off, and may be seen rumiing about Avingless. According to Gould, an early English obserA^er, the eggs destined to hatch the future females, males and workers, are deposited at three different periods. The nests of some species of Formica are six feet in diameter FOUMICAUI^. 181 and contain many thousand individuals. Ants also build nests of clay or mud, and inhabit hollow trees. They enjoy feeding upon the sweets of flowers and the honey of the Plant- lice, which they domesticate in their nests. Several species of beetles, including some of the Staphylinidce ^ take up their abode in ants' nests. Ants are useful as scavengers, feeding on decaying animal matter. A good method of obtaining the skeletons of the smaller animals, is to place them on a densely populated ant-hill. The habits of the ants, their economy and slave-making habits, are described in the works of Huber, La- treille, and Kirbj^ and Spence. Upwards of a thousand species of ants have alread}^ been described ; those of this country have still to be monographed. The first group of this extensive family consists of Dorylus and its allies, and Formica and the neighboring genera, all of which are distinguished by having only the first abdominal seg- ment contracted, while in the second group {Ifynnicarice), the two basal rings are contracted into knot-like segments. The genus Dorylus was, by Latreille, King, and others, in- cluded in the Mntillarim . The head is very short, the ocelli are large and glolndar. The thorax and abdomen are elongated, the last is cylindrical, with a small, round, basal joint. The legs are short, with broad compressed femora and feather-like tarsi. In the wings the outer subcostal cells are wanting. The females are not yet known. Mr, F. Smith says that Dorylus was found by Hon. W. Elliot to live in the man- ner of ants, under the stone foundation of a house in India. The society was very numerous. The difference in size of the male and worker is yevy remarkable. The males are of large size and are found in tropical Asia and Africa. TypMopone is an allied genus. T. p>aUipes Ilaldeman is found in Pennsylvania. To the genus Anomma belong the Driver-ants of "Western Africa. They march in vast armies, driving everj'thing before them, so formidable are they from their numbers and bite, though they are of small size. They cross streams, bridging them by their interlocked bodies. Only the workers are known. Two species only, A. Burmeisteri Shuckard, and A. arcens Westwood, are described from near Cape Palmas, West Africa. 182 HY3IENOPTERA. The genus Ponera is found disti'ibuted throughout the tropics. Tlie females and workers are armed vvitli spines ; the abdomen is elongated, the segments more or less diminished in size, the first comparatively large and often cubical. The legs are slender. P. ferrnginea Smith is a Mexican species. The allied genus Odontomachus springs like some leaping spiders. It uses for this purpose its unusually long mandibles, which are bent at right angles. 0. clarus Koger lives in Texas. Formica includes the tj'pical species of ants. Over two hun- dred species of this genus have been already described. The body is unarmed. The abdomen is short, oval or spherical, the scale-like first segment being lenticular in form, with a sharp upper edge. The subcostal cell of the fore-wings ends in a point. Formica scmguinea Latr. is one of our most abundant species, making hillocks of sand or clay, according to the nature of the ground. From the formicary walks, and underground galleries, radiate in all directions. This species has been 'ob- served making forays upon each others colonies. We have found a variety of this species in Labrador, where it is com- mon. It does not throw up hillocks, but tunnels the earth. This species has been observed in Europe by P. Iluber, to go on slave expeditions. They attack a " negro-colonj^ " be- longing to a smaller black species, pillaging the nest, and carry- ing olf merely the larvas and pupoe. The victors educate them in their own nests, and on arriving at maturity the negroes take the; entire care of the colony. Polyergus rufescens is also a slave- making ant, and " Latreillc very justly observes that it is physi- cally impossible for the rufescent ants {Polyergus rufescens), on account of the form of their jaws, and the accessory parts of their mouth, either to prepare habitations for their family, to procure food, or to feed them." Formica savgimiea sallies forth in immensely long columns to attack the negTo ant. Hu- ber states that only fixe or six of these fora3s are made within a period of a month, at other seasons they remain at peace. Iluber found that the slave-making Polyergus rufescens when left to themselves perish from pure laziness. They are waited upon and fed by their slaves, and when the}- are taken away, their masters perish miserably. Sometimes they are known to labor, and were once observed to carry their slaves to a spot chosen rORMICARI^. 183 for a nest. The 7^. sanguinea is not so helpless, "they assist their negroes in the construction of their nests, they collect their sweet Uuid from the Aphides ; and one of their most nsnal occupations is to lie in wait for a small species of ant on which they feed ; and when their nest is menaced by an enemy they show their value for these faith- ful servants, by carrying them down into the lowest apartments, as to a place of the greatest security." (Kirby.) Pupae of both of the slave- making species were placed in the same formicary by Huber, Avhere they ¥ig. no. were reared l>y the "negroes," and on arriving at maturity " lived together under the same roof in the most perfect amity," as we quote from Kirby. Darwin states that in England, F. sanguinea does not enslave other species. In this country Mr. J. A. Allen has described in the Proceedings of the Essex Institute, vol. 5, 18GG, a foray of a colony of F. sanguinea upon a colony of a black species of Formica, for the purpose of making slaves of them. Formica Pensylvanica^ our largest species, is found in oaks and decay- Fig. 111. ing trees, while F. lierculanea Latr. burrows in the earth, its hole opening beneath stones and sticks. Gould, who wrote in 1747, states that there are two sizes of workers of the common European Formica rvfa, and flava; one set of individuals exceeding the other by about one-third. Kirby states that in his specimens "the large workers of For- mica rufa are nearly three times, and of F. flava^ twice the size of the small ones." Mr. E. Norton describes F. fulvacca (Fig. 110, worker minor), and also Tapinoma tomentosa (Fig. Ill, worker major; antenniie broken off), from Mexico. The tropical genus Pobp-hachis includes, according to Smith, all those species that closely resemble Formica, but which 184 HYMENOPTERA. have the thorax and node of the peduncle armed with spines or hooks. They construct small semicircular nests, of a kind of net-work, on the leaves of trees and shrubs. Their communities are small, sel- dom exceeding twenty individuals. Mr. Norton describes P. arhoricola (Fig. 112, worker major) from Mexico. An allied genus is Ectatomma (Fig. 113, worker major of E. ferrnginea Norton, from Mexico), Mr. F. Smith has described a new genus, (EcojyhyUa, which is allied to Formica. They are green ants, found building in trees in the tropics of the old world. The nest of (E. smaragdina Smith is "formed by drawing together a number of green leaves, Avhich they unite with a fine web. Some nests are a foot in diameter. They swarm, says Mr. Wallace, in hilly for- ests in New Guinea. Their sting is not very severe. This genus forms a link between Formica and Myrmica ; it agrees with the former in hav- ing a single node to the pe- duncle, and with the latter in having the ocelli obsolete in the workers, and in being fur- nished with a sting." The curious Iloney-ant of Texas and Mexico, 3Ti/rmeco- cystus Mexicanus Westwood, has two kinds of "workers of very distinct forms, one of llie usual shape," according to Smith, " and performing the F'S- ii''^- active duties of the formica- rium ; the other and larger worker is inactive and does not quit the nest, its sole purpose, apparently, being to elaborate a kind of honc}^, which they are said to discharge into prepared recep- tacles, which constitutes the food of the entire population of the community. In the honey-secreting workers the abdomen is distended into a large globose bladder-like form. From this honey an agi'eeable drink is made by the Mexicans." FORMICAEI^. 1^5 The second subfamily, Myrmicarice, includes those species in which the two first abdominal segments are contracted and lenticular. In Myrmica the females and workers are armed with spines, and tlie ocelli are absent in the worl^ers. The species are very small, and mostly bright colored. Myrmica molesta Say is found in houses all over the Avorld. G. Lincecum describes the habits of the Agricultural Ant of Texas, Myrmica molefaciens. It lives in populous communi- ties. "They build paved cities, construct roads, and sustain a large military force." In a year and a half from the time the colony begins, the ants previously living concealed beneath the surface, appear above and "clear away the grass, herbage, and other litter, to the distance of three or four feet around the entrance to their city, and construct a pavement, .... con- sisting of a pretty hard crust about half an inch thick," formed of coarse sand and grit. These pavements Avould be inun- dated in the rainy season, hence, " at least six months pre- vious to tlie coming of the j-ain," they begin to build mounds rising a foot or more from the centre of the pavement. Within these mounds are neatly conotructed cells into which tlie "eggs, young ones, and their stores of grain, are carried in time of rainy seasons." Xo green herb is allowed to grow on the pavement except a grain-bearing grass, Aristida stricta. This grain, when ripe, is harvested, and the chaff removed, while the clean grain is carefully stored aAvay in dry cells. Lincecum avers that the ants even sow this grain. They also store up the "grain from several other species of grass, as well as seeds from many kinds of herbaceous plants." Pheidole is distinguished by having workers with enormous heads. P. notabilis Smith, from the Island of Bachian, Indian Archipelago, is noted for the enormously enlarged, cubical head of the worker major, which is at least six times the size of the abdomen, while in the worker minor, the head is of the ordinary size. An Indian species, P. providens Westwood, accordhig to Col. Sykes, "collects so large a store of grass seeds as to last from January and February, the time of their ripening, till Octobar." The genus Atta is also well-armed, while the workers have a very large, deeply incised and heart-shaped head, without 186 HYMENOPTERA. ocelli, and the second abdominal knot-like ring is very trans- verse. A. dypeata Smith is a Mexican species. ^ In Eciton the man- dibles nearly equal the length of the in- sect itself. This ge- nus is the most ferocious of all the ants, entering the nest of species of Formica and tearing them, limb from limb, and then carrying off the remains to their own houses. Eciton Mexicana Roger (Fig. 114, worker major, a, front view of head, show- Fig, lu. ing the immense sickle-like mandibles, and only the two basal joints of the antenn:i3 ; Fig. 115, worker minor, with a front view of the head, showing the mandi- bles of the usual size). This species, with Eciton Snmiclirasti Norton, (Fig. IIG, worker minor) has been found by Professor Sumichrast at Cordova and Orizaba, Mexico. The males of Eciton are not 3'et known. .Smith supposes that JMbidns (a genus allied to Dorylus) is tlie male form, and Sumi- chrast thinks this conjec- ture is "sustained by the fact that it is in the season when the sorties of the Eciton are the more frequent that the Labidus also show themselves." FOKMTCARIiE. 187 An allied genus is Pseudomyrma. P. hicolor GiK-rin (Fio-, 117) is found in Central America. P.flacidala Sniitli, found in Central and South America, in Mexico lives, according to Sumichrast, within the spines which arm the stems of certain species of Mimosa. These spines, fixed in pairs upon the branches, are pierced near the end by a hole (Fig. II80), which serves for the entrance and exit of the ants. The genus (Ecodoma differs from Atta in having the thorax armed with spines. (27. Fig. iig. Mexicana Smith (Figs. 119, female; 120, worker major) is abundant on the Gulf Coast of Mexico. In manj^ places, ac- cording to Sumichrast, the natives eat the females after hav- ing detached the thorax. The intelligence of these ants is wonderful. They are seen in immense num- bers transporting leaves. Sumichrast states that "the ground at the foot of the tree, where a troop of these ' arrieras,' or workers, is assembled for despoil- ing it of its leaves, is ordinarily strewn with frag- ments cut off with the greatest precision. And if the tree is not too lofty, one can satisfy himself that a party of foragers, which have climbed the tree, occupies itself wholly in the labor of cutting them off, while at the foot of the tree are the carriers which make the journeys between the tree and the nest. This manage- ment, which indicates among these a insects a rare degree of intelligence, is, perhaps, not a constant and in- variable practice, but it is an incon- testable fact, and one which can be constantly proved." "It is specially in the argillaceous countries that the CEcodomas build their enormous formicaries, so that one perceives them from afar by the projection which they form above the level of the soil, as well as by the absence of vegetation in their immediate neighborhood. These nests occupy a surface of many square Fi-. 117 118. 188 HYMENOPTERA. metres,* and their depth varies from one to two metres. Very many openings, of a diameter of about one to three in- ches, are contrived from the exterior, and conduct to the innei- cavities vvliicli serve as storehouses for the eggs and Larva". The central part of the nest forms a sort of funnel, designed for the drainage of water, from which, in a country where the periodical rains are often abundant, they could hardly es- cape Avithout be- ing entirely sub- merged, if they did not provide for it some out- let. "The s^^stein which reigns in Fig. 119. tlie interior of these formicaries is extreme. The collection of vegetable debris brought in by the Avorkers is at times considerable ; but it i.i deposited there in such a manner as not to cause an_v inconvenience to the inhabitants, nor impede their circulation. It is mostly leaves whicli are brought in from without, and it is the almoot excluLiivo choice of this kind of vegetation which makes the Gilcodoma a veritable scourge to agTiculture. At each step, and in almost every place in the elevated woods, as on the plains ; in desert places as well as in the nciglil)orhood of habitations, one meets numerous columns of these insects, occupied with an admirable zeal in the transportation of leaves. It seems even that the great law of the divi- Fig. 120. sion of labor is not ignored by these little creatures, judging from the observations which I have often had occasion to make." (Sumichrast.) "The CE'. ccpkalotes" says II. W. Bates, "from its immense numbers, eternal industiy, and its plundering propensities, be- comes one of the most important animals of Brazil. Its immense hosts are unceasingly occupied in deibliating trees, and those most relished by them are precisely the useful kinds. They * A metre is about thirty -nine (39.37) inches. FORMICAEI^. 189 have regular divisions of laborers, numbers mounting the trees and cutting otf the leaves in irregularl}- rounded pieces the size of a shilling, another relay carrying them off as they fall." ''The heavily laden fellows, as they came trooping in, all de- posited their load in a heap close to the mound. About the mound itself were a vast number of workers of a smaller size. The very large-headed ones were not engaged in leaf-cutting, nor seen in the processions, but were only to be seen on dis- turbing the nest." Bates also says, "I found, after removing a little of the surface, three burrows, each about an inch in diameter ; half a foot downward, all three united in one tubular burrow about four inches in diameter. To the bottom of this I could not reach wlieu I probed Avith a stick to the depth of four or five feet. This tube was perfectly smooth and covered with a vast number of workers of much smaller size than those oc- cupied in conveying the leaves ; the}' Avere unmixed Avith an}' of a larger size. AfterAvards, on probing loAver into the bur- row, up came, one by one, seA'eral gigantic fellows, out of all l)roportion, larger than the largest of those outside, and Avhich I could not have supposed to belong to the same species. Be- sides the greatly enlarged size of the head, etc., they have an ocellus in the middle of the forehead ; this latter feature, added to their startling appearance from the cavernous depths of the formicariuni, gaA'e them quite a Cyclopean character." Of another species, the (Ec. sexdeutata, Mr. Smith quotes from Rev. Ilamlet Clark, that at Constancia, Brazil, the pro- prietor of a plantation used e\erj means to exterminate it and failed. " Sometimes in a single night it will strip an orange or lemon tree of its leaves ; a ditch of water around his garden, Avhich quite keeps out all other ants, is of no use. This spe- cies carries a mine under its bed without any difficulty. In- deed, I haA'e been assured again and again, by sensible men, that it has undermined, in its progress through the country, the great river Paraiba. At any rate, without anything like a nat- ural or artificial bridge, it appears on the other side and con- tinues its course." This testimou}^ is confirmed by Mr. Lincecum (Proceedings of Academ.y of Katural Sciences, rhiladelphia, 1867, p. 24) in an interesting account of the (Ec. Texana, Avhich he has obserAcd for eighteen years. lie states 190 HYMENOPTEIIA. that they often carry then- subterranean roads for several hun- dred yards in grassy districts, where the grass would prove an impediment to tlieir progress. On one occasion, to secure ac- cess to a gentleman's garden, where they were cutting the vegetables to pieces, they tunnelled beneath a creek, which was at that place fifteen or twenty feet deep, and from bank to bank about thirty feet. He also observes that the smaller workers which remain around the nest do not seem to join in cutting or carrying the leaves, but are occupied with bringing out the sand, and generally work in a lazy waj', very differently from the quick, active leaf-cutters. Also, that the pieces of leaves are usually dried outside before being carried in, and that if wet b}^ a sudden shower are left to decay Avithout. He also thinks that their lives are dependent upon access to Avater, and that the}' always choose places where it is accessible by digging wells. In one case, a well was dug by Mr. Pearson for his own use, and water found at the depth of thirty feet. The ant-well which he followed was twelve inches in diameter." Fig. 121. (Norton, American Naturalist, vol. 2.) The genus Cryptocerns is remarkable for its flattened head, with the sides expanded into flattened marginal plates, con- cealing, or partly hiding the e3'es. C mult 182)1)108118 Norton (Fig. 121) is the most common species about Cordova, Mexico, where they live, according to Sumichrast, within the trunks of trees. CiiRYSiDiD^ Latreille. In this small group the thirteen- jointed antenme are elbowed, the eyes are oval and the ocelli distinct. The maxillary palpi are five, and the labial palpi three-jointed. There are about four hundred species known. Tliese insects are very diff'erent from the ants in their oblong compact form, their nearly sessile, oblong abdomen, having only three to five rings visible, the remaining ones being drawn with- in, forming a long, large, jointed sting-like ovipositor, which can be thrust out like a telescope. The abdomen beneath is concave, and the insect can roll itself into a ball on being dis- turbed. They are green or black. The sting has no poison- bag, and in this respect, besides more fundamental characters, CHRYSIDID^. 191 the Chrysis family approaches the Ichneumons. They best merit the name of "Cuckoo-flies," as they fly and run briskly in hot suuGliiue, on posts and trees, darting their ovipositor into holes in search of the nests of other Hymenoptera, in which to lay their eggs. Their larvne are the first to hatch and devour the food stored up by other fossorial bees and wasps. "St. Fargeau, however, who has more carefull3' examined the econ- omy of these insects, states that the eggs of the Chrysis do not hatch until the legitimate inhabitant has attained the greater part of it 3 grovvth as a larva, when the larva of the Chrysis fastenj on it3 back, sucks it, and in a very short time attains its full size, destroying its victim. It does not form a cocoon, but remains a long time in the pupa state." (Westwood.) "In the Entomological Magazine has been noticed the dis- covery of Iledychrum bidentulum, which appears to be parasitic upon Pseu caliginosus ; the latter insect had formed its cells in the straws of a thatched arbor, as many as ten or twelve cells being placed in some of the straws. Some of the straws, per- haps about one in ten, contained one or rarel}^ two, of the Hedychrum, placed indiscriminately amongst the others. Walkcnaer, in his Memoirs upon Ilalictus, informs us that Hedychrum lucidulum waits at the mouth of the burrows of these bees, in order to deposit its eggs therein ; and that when its design is perceived by the bees, they congregate together and drive it away. St. Fargeau states that the females of Hedychrum sometimes deposit their eggs in galls, while II. regiura oviposits in the nest of Megachile muraria ; and he mentions an instance in which the bee, returning to its nearly finished cell, laden with pollen paste, found the Hed^X'hrum in its nest, which it attacked with its jaws ; the parasite im- mediately, hovrcver, rolled itself into a ball, so that the Mega- chile was unable to hurt it ; it, however, bit off its fom- wings which were exposed, rolled it to the ground and then deposited its load in the cell and fiew away, whereupon the IIed3'chrum, now being wingless, had the persevering instinct to crawl up the Avail to the nest, and there quietly deposit its egg, which it placed between the pollen paste and the wall of the cell, which prevented the Megachile from seeing it." (Westwood.) In Cleptes the underside of the abdomen is not hollowed out ; 192 HYMENOPTERA. it is acutely oval, and with five rings in the male. Cleptes semiaurata Latr. is found in Central Europe. We have no na- tive species. In Chrysis and the other genera, Stilbum, Parno- pes, and Iledychrum, the abdomen is hollowed beneath, and the tip is broad and square. Chrysis hilaris Dahlb. (Fig. 122) is a short, thick, bluish green species, .32 inch in length. It is not uncommon in New England. In Iledychrum the maxillary palpi and ligula are rather short, the last cordate ; the mandibles are three-toothed v.ithin. The abdomen is broad and short, almost spherical, the second seg- ment being the largest. //. dimidiatmn Say is found in the Middle States. The European Stilbum spJendidum, Fabr. according to Du- four, lives in the cells of Pelopieus spirifex. It makes oblong ,,;,.»><^,=^ cocoons of a deep brov.n, with rounded J^^^^^^^g^^^ end.s ; they are of great tenacity, being mixed with a gummy matter. Mr. Guenzius states that in Port Natal ''a species of Stilbum lays its eggs on the collected caterpillars stored up b}'^ Eumenes tinctor, which con- structs a nest of mud and attaches it to reeds, etc., not in a single, but a large mass, in which cells are excavated, similar to the nest of Chalicodoma micraria?* First, it uses its ovi- positor as a gimlet, and when its point has a little penetrated, then as a saw or rasp ; it likewise feels with its ovipositor, and, finding an unfinished or an empt}' cell it withdraws it immedi- atel3% without la^'ing an egg." IcHNEUMONiD^. Lati-cille. The Ichneumon-flies are readily recognized by the usually long and slender body, the long ex- serted ovipositor, which is often very long, and protected by a sheath formed of four stylets of the same length as the true ovipositor. The head is usually rather square, with long, .slender, rnany-jointed antennrj which are not usually elbowed. The maxillary palpi are five to six-jointed, while the labial *A query (?) after the name of a species indicates a doubt wiiether the insect realiy belongs to that species; so with a ? after the name of a jrcnus. A ? before both the genus and species expresses a doubt whether tliat be the insect at all. ICHNEUMONIDiE. 193 pa\pi are three to four-jointed. The abdomen is inserted im- mediately over tlie liind pair of trochanters, and usually consicts of seven visible segments. The fore-wings have one to three subcostal (cubital) cells. The larva is a soft, fleshy, cylindrical, footless grub, the rings of the body being moderatel}^ convex, and the head rather smaller than in the foregoing families. The eggs are laid by the parent either upon the outside or within the caterpillar, oi other larva, on which its young is to feed. When hatched it devours the fiitty portions of its victim which dies gradually of exhaustion. The ovipositor of some species is very long, and is fitted for boring through very dense substances ; thus Mr. Bond, of England, observes that BJn/ssa persuasoria actually' l)ores through solid wood to deposit its eggs in the larvae of Sirex ; the ovipositor is Avorked into the wood like an awl. When about to enter the pupa state the larva spins a cocoon, consisting in the larger species of an inner dense case, and a looser, thinner, outer covering, and escapes as a fly through the skin of the caterpillar. The cocoons of tlio smaller genera, such as Cr3'ptus and Microgaster, may be found packed closely in considerable numbers, side by side, or sometimes placed up- right within the l)ody of caterpillars. The Ichneumon-flies are thus very serviceable to the agricul- turist, as they must annually destroy immense numbers of cat- erpillars. In Europe over" 2,000 species of this family have l)een described, and it is probable that we have an equal num- ber of species in America ; Gerstaecker estimates that there are 4,000 to 5,000 known species. The Ichneumons also prey on certain Coleoptera and Ilymen- optera, and even on larvre of Pliryrjanidce, which live in the water. In Europe, Pimpla Fairmairii is parasitic on a spider, ('lubione holosericea, according to Laboulbcne. Boheman states that P. ovivora lives on a spider, and species of Pimpla and Hemiteles were also found in a nest of spiders, according to Gravenhorst. Bouche says that Pimpla rufata devours, during winter and spring, the eggs of Aranea diadema, and Ratzburg gives a list of fourteen species of Ichneumons parasitic on spiders, belonging to the genera Pimpla, Pezomachus, Ptero- malus, Cryptu3, Hemiteles, Microgaster, and Mesochorus. Mr. 13 194 HYMENOPTERA. Emerton informs me that he has reared a Pezomachus from the egg-sac of Attus, whose eggs it undoubtedly devours. They are not even free from attacks of members of their own family, as some smaller species are well known to prey on the larger. Being cut off from communication with the external world, the Ichneumon larva breathes by means of the two principal trachese, which terminate in the end of the body, and are placed, according to Ger- staecker, in com- munication with a stigma of its host. From the com- plete assimilation ^^ of the liquid food. Fig. 123. the intestine ends in a cul de sac, as we have seen it in the larva; of Humble-bees and of vStj'lops, and as probably occurs in most other larva; of fjimilar habits, such as young gall-flies, weevils, etc., which live in cells and do not eat solid food. The first subfamily, the Evaniidai, are insects of singular and very diverse form, in which the antenrse are either straight or elbov/ed, and thirteen to fourteen- joiuted ; the fore-wings have one to throe subcostal (cubital) cells, and the hind wings are almost without veins. In Evania and Foznus the abdomen has a very slender pedicel, originating next the base of the metanotnm. The former genus has a remarkably short triangular compressed abdomen in the female, but ovate in the male. The species are parasitic on Blatta and allies. Olivier (Fig. 123, J and pupa) is a black species, and is para- sitic on the cockroach, Periplaneta, from the eggs of which we have taken the pupa and adult. The eggs of the cockroach are just large enough to accommodate a single Evania. This species Fig. 124. Evania loivigata ICHNEUMOXIDJE. 195 is widely distributed, and in Cuba, according to Cresson, it devours tlie eggs of Periplaneta Americana. The genus Aulacodes of Cresson, "forms a very close con- necting-link between the minute Ichneumons and the Elvaniae," A. nigriventris Cresson (Fig. 124, a; 6, metathorax ; c, inser- tion of the abdomen) lives in Cuba. Fortius is quite a different genus, as the abdomen is very long and slender. Foenus jaculator Linn, is known in Europe to frequent the nests of Crahronid(i2 , ovipositing in the larvae. Pelecinus is a fa- miliar insect, the im- mensely elongated, linear abdomen of -^ j i % the female easily Fig. 125. distinguishing it. The male is extremely rare ; its abdomen is short and clavate. It strikingly resembles Trypoxylon, though the abdomen is considerably larger, Pelecinus poly- cerator Drury (Fig. 125, $ and ?) is widely distributed throughout this country. The genuine Ichneumonidce have long, straight, multiarticu- late antennae. The first subcostal (cubital) cell of the fore- wings is united with the median cell lying next to it, while the second is very small or wholly wanting. There arc two recurrent veins. Mr. Cresson has described the genus EipJiosoma (Fig. 126), Tig. 126. which he states may be known by the long, slender, compressed abdomen, and the long posterior legs, with their femora toothed beneath the tips. E. annu- latum Cresson, a Cuban species, is, according to Poe}^, "para- sitic upon a larva of Pyralis." (Cresson.) In Ophion the antennae are as long as the body, the abdo- men is compressed, and the species are honey-yellow in color. 0. macrurum Linn. (Fig. 127) attacks the American Silk- worm, Telea Polyphemus. Anomalon is a larger insect and usuall}^ black. A. vesparum is, in Europe, parasitic on Vespa. 196 HYMENOPTERA. The genus E7ii/ssa contains our largest species, and frequents the holes of boring insects in the trunks of trees, inserting its remarkably long ovipositor in the bod^^ of the larvae deeply embedded in the trunk of the tree. Harris states that Rhyssa (Pimpla) atrata and lanator (Fig. 128, male) of Fabricius, " may frequently be seen thrusting their slender borers, measur- ing from three to four in- ches in length, into the trunks of trees inhabited 1)3' the grubs of the Tre- mex, and by other wood- ^'"'S- ^27. eating insects ; and, like the female Tremex, they sometimes become fastened to the trees, and die without lieing able to draw their borers out again." The abdomen of the male is A'ery slender. Pimiila has the ovipositor half as long as the abdomen. P. pedalis Cresson is a pararjite on Clisiocampa. The genus Trogns leads to Ichneumon. The antennoe are shorter than the body ; the abdomen is slightly petiolate, fusi- form, and the second subcostal cell is quadrangular. Trogus exssoriiis Brulle is tawny red, and is a para- site of Papilio Asterias. The genus Ichneumon (Fig. 120) is one of great extent, probably containing over three hundred spe- cies. The abdomen is long and slender, lanceolate ovate, slightly petiolate. The second subcostal cell is five-sided, and the ovipositor is either concealed or slightly exscrted. Fig. 128. [clineumon suturalis Sa}' is a very common form, and has been reared in abundance from the larva of the Army- worm, Leu- cania unipuncta. The body is pale rust-red, with black sutures on the thorax. Another common species, also parasitic on the ICHNEUMONID^ . 197 Fiff. 129. Army-worm, is the Ichneumon paratus, which is blackish, banded and spotted with yellow. The singular genus Grotea, established by Mr. Cresson, has along and narrow thorax (Fig. 130a), and a very long and petiolated abdomen (c). We have taken G. angiuna Cresson, the only species known, from the cells of Crabro in raspbeny stems received from Mr. Ingus. Cryptus is a genus of slender form, with a long, cylindrical abdo- men, which is petiolate. In the fe- male it is oval with an exserted ovipositor. Cresson ligures a Aving (Fig. lol) of C? ornatipennis, a Cuban species, which has the wings dilterently veined from the other species. Westwood I'cmarks that in Europe a species of this genus preys on the larva; of the Ptinidoi. Pezomachus is usually "wingless, and might at first sight read- il}^ be mistaken for an ant. The body is small, the oval abdo- men petiolate, and the wings, when j)re8- y^ ~~~\^^ — z:>-^ ent, are very pniall. The species are very numerous. Gersta^cker suggests that some may be wingless females, belong- ing to winged males of allied genera. The third subfamily is the Braconidce , containing those genera having long multiarticulate antennte, and Avith the first subcostal cell separate from the first median, lying just behind it. The second subcostal cell is usually largo, and there is onty one recurrent vein. The genus Bracon is distinguished by the deeply excavated clypeus. The first sub- costal cell is completely formed behind, wanting the recurrent nerve ; the second cell is long, and four-sided. More tluui five hundred species, mostly of bright, gay colors, are already known. The genus RhopaJosoma of Cres- son connects Bracon and other minute genera (Braconidae) with the true Ichneumons. R. Poeyi Cresson (Fig. 132) is a 198 HYMENOPTERA. pale honey-yellow species, with a long club-shaped abdomen. It lives in Cuba. Rogas is a genus differing from Bracon in having the three first abdominal j-ings long, forming a slender petiole. In Microgaster, a genus containing numerous species, the antenuae are eighteen-jointed, and the abdomen is shorter than usual, and clavate. There are two or three subcostal cells, the second very small. 3Ii- crogaster neplio})tericls (Plate 3, figs. 3, 3 a) is parasitic on Nephopter^'x Edmandsii, found in the cells of the Humble-bee. Aphidias^ the parasite of the Plant-lice, is a most A'aluable ally of man. It is known by its small size, and by having the second and third segments of the abdomen moving free on Fig. 132. each other. There are three cubital cells, though the wings are sometimes wanting. Aphidius (Praon) avena- pMs of Fitch, the Oat-louse Aphidius, is black with honey- yellow legs, and is one-tenth of an inch long. Ajjhidiv.s (Toxares) triticapMs Fitch, the Wheat-louse Aphidius, is black, shining, with thread-like antennae composed of twenty-five joints. Its length is .08 inch. Frequently the large size of the parasite causes the body of the dead Aphis to SAvell out into a globular form. Pkoctotkypid^ (Proctotri(pn) Latreille. Egg-parasites. In this family are placed very minute species of parasitic Ich- neumon-like Hymenopters which have rather long and slender bodies, with straight or elbowed antenna of various lengths, often haired on the joints, usually teu to fifteen, sometimes only eight in number, while the wings are covered with minute hairs and most of the nervures arc abseut. The maxillary palpi are three to six, the labial palpi usually three-jointed. The abdo- men has from five to seven joints, and the tarsi are mostly five- jointed, rarely four-jointed. These insects are often so minute that they can scarcely be distinguished by the naked eye unless it is specially trained; they are black or brown, and very active in their habits. They may be swept off" grass and herbage, from aquatic plants, or from hot sand-banks. They PROCTOTRYPID^. 199 prey on the wheat-flies by inserting their eggs in their larvse, on gall-midges, and gall-flies, and on fungus-eating flies. In Europe, species of Teleas lay their eggs in those of other insects, especially butterflies and moths and hemipters, where they feed on the juices of the larvae growing within the egg, coming out as perfect Ichneumons. We probably have many species of these insects in this country. They usually occur in great numbers where they are found at all. They are almost too small to pin, and if transfixed Avould be unfit for study, and should, therefore, be gummed on mica, or put into small vials with alcohol. In Proctotnqjes the antennae are long, feathered, twelve- jointed. The fore-wings have the beginning of a cubital cell, and two longitudinal veins on the posterior half. Tlie abdo- men is spindle-shaped and very acutely pointed, the terminal joints being tubular in their arrangement, and thus, as Westwood states, approaching the Chrys i didce. An unknown species (Fig. 133) we have taken at the Glen, in the White Mountains. ,'V\ The head of Diapria is horizontal and Fig. 133. longer than broad ; the ocelli are moved forward on to the front edge ; the long, filiform antenuiie have a projection on the under side, with the basal joint much elongated ; in the male they are thirteen or fourteen-jointed, Avith one joint less in the female. The wings are without stigma or veins. The abdomen is long, oval, pedicelled. In Europe, D. cecidomyi- arum Bouche is parasitic on the larvae of Cecidomyia arte- misiae. Esenbeck considers that this genus is also parasitic on the earth-inhabiting Tipxilidfe. Gonatopus is a wingless genus, with the head very broad, transverse, and the front deeply hollowed out, while the ten- jointed antennae are long, slightly clavate, and the thorax is much elongated, deeply incised, forming two knot-like portions. Goyiatopus lunatus Esenbeck, found in Europe, is one and a half lines long. Ceraphron has the antennae inserted near the month ; they are elbowed, and eleven-jointed in the male, and ten-jointed in the female. The abdomen has a very short pedicel. The fore- fOO HYMENOPTERA. wings have a very short, bent costal (radial) vein. C. armoh turn Say was described from Indiana. The egg-parasite, Teleas, has the elbowed twelve-jointed an- tennae inserted very near the front of the head, and slightly hairy and simple in the male, but in the female terminated in a six-jointed club. The thorax is short, the legs thickened and adapted for leaping, and the abdomen is pedicelled. Many species have been found in P^urope. According to Westwood, "the type of this genus is the Ichneumon ovulorum of Linnaeus {Teleas Linncei Esenbeck), which Linnaeus and D3 Geer obtained from the eggs of moths." It has been raised from the eggs of several Bom- hiicicla',. "Bouchs observed the female deposit Fig. 134. ail egg in each of the eggs of a brood of Bom- byx neustria. lie describes tlie larva as elliptical, white, shilling, rugose, subincurved, and one-third of an inch long." (Westwood.) Of the extensive genus Platygaster over a hundred European species are already known. The body, especially the abdomen, is generally flattened, the antennae are ten-jointed, and in the female clavate. The wing veins are absent ; the rather slender legs are not adapted for leaping, and the tarsi are five-jointed. A species of Platygaster (Fig. lo-t) not 3'et named, oviposits in the eggs of the Canker-worm moth, Anisopteryx A'ernata. and by its numbers does much to check the increase of this caterpillar. AVe have seen several of these minute insects engaged in inserting their eggs into those of the Canker- worm. Dr. Harris, in speaking of the enemies of the Ilessian-fly, states, that "two more parasites, Avhicli Mr. Herrick has not yet described, also destroy the Hessian-fly, while the latter is in the flax-seed or pupa state. Mr. Herrick says, that the egg- parasite of the Hessian-fly is a species of Platygaster, that it is very abundant in the autumn, when it lays its own eggs, four or five together, in a single cg^ of the Hessian-fly. This, it appears, does not prevent the latter from hatching, but the maggot of the Hessian-fly is unable to go through its trans- formations, and dies after taking on the flax-seed form. Mean- while its intestine foes are hatched, come to their growth, spin PROCTOTRYPID^. 201 themselves little brown cocoons within the skin of their victim, and in due time, are changed to winged insects, and eat their way out." P. error Fitcii (Fig. 135) is closely allied to P. tipukti Kirby, which, in Europe, destroys great numbers of the Wheat-midge. Whether this is a parasite of the midge, or not, Dr. Fitch has not 3-et determined. The habits of the genus Betlujias remind ns of the fossorial wasps. Bethylus fuscicornis, according to Haliday, "buries the larviB of some species of Tinea, wliich feed upon the low tufts of Rosa spinosissima, dragging them to a considerable distance with great labor and solicitude, and employing, in the instance recorded by Mr. llaliday, the bore of a reed stuck in the ground instead of an arti- ficial funnel, for the cells which should contain the progeny of the Bethylus, Avith its store of provision." (Westwood.) The genus Inostemma is re- markable for having the basal segment of the abdomen of the females furnished with a thick curved horn, which extends over the back of the thorax and head. Dr. Fitch states that 7. viserens is supposed by Kirliy to insert its eggs into those of tlie Wheat-midge. In tlie gemis Galesus of Curtis, the mandibles are so enlarged and length- ened as to form a long beak, and Westwood farther states that in some specimens the anterio-r wings have a notch at the ex- tremity. Sa^-'s genus Coptera has similar Avings. C. polita Say was disco^'ered in Indiana. In the very minute species of Mijmar and its allies, the head is transverse, with the antennte inserted above the middle of the fiice ; they are long and slender and elbowed in the male, but clavate in the female. There are no palpi, while the very narrow wings have a very short subcostal vein and on the edges are provided with long dense cilia?. The antennse of Mymar are thirteen-jointed in tlie male, and nine-jointed in the female ; the club is not jointed. The tarsi are four-jointed. and the abdomen is pedunculated. 3Tymar piiJdieUvs Curtis is a quarter of a line long. It is found in Europe. An allied 202 HYMENOPTERA. form Polynema ovulorum Linu. lays numerous eggs in a single butterfly's egg. In Anaphes the male antennae are twelve-jointed, those of the female nine-jointed, and the abdomen is subsessile and ovoid. In Anagrus the male antennae are thirteen-jointed, those of the female nine-jointed, while the tarsi are four-jointed, and the acutely conical abdomen is sessile. No native species are known. The smallest Ilj-menopterous insect known, if not the most minute of all insects, is tlie Pteratumus Putnamii Pack. (Plate 3, figs. 8, 8a, hind wing), Avhich we first discovered on the body of an Anthophorabia in the minute eggs of which it is undoubtedly parasitic. It differs from Anagrus in the obtusely conical abdomen, and the narrower, very linear wings, which are edged with a fringe of long, curved hairs, giving them a graceful, feathery appearance. The fore-wings are fissured, a very interesting fact, since it shows the tendency of the wings of a low Hymenopterous insect to be fissured like those of Pterophorus and Alucita, the two lowest Lepidop- terous genera. It is one-ninetieth of an inch in length. CiiALCiDiD/E Westwood. This is a group of great extent ; the species are of small size ; they are often of shiny colors, as the name of the principal genus implies, being eitlier bronzen or metallic. Tliey have also elbowed antennjie with from six to fourteen joints, and the wings are often deficient in veins. In some genera, including Chalcis, the hind thighs are thickened for leaping. The diff'erences between the sexes, generally very marked in Ilymenoptera, are here especially so. The abdo- men is usually seven-jointed in the male and six-jointed in the female, the other rings being aborted. The male of several species has the joints of the antenuje swelled and furnished with long hairs above. Some of the species of Pteromalus are wing- less, and closely resemble ants. They infest eggs and larvae. Some si)ecies prey upon the Aphides, others lay their eggs in the nests of wasps and bees. One species is known in Europe to be a parasite of the common house-fly. Others consume the larvcB of the Hessian-fly, and those Cecidomyiae that pro- duce galls, and also the true gall-flies (Cynips). Some are CHALCIDID^. 203 parasites on other Ichneumon parasites, as there are species preying on tlie genus Aphiclius, which is a parasite on the Aphis. Mr. Walsli lias bred a species of Hockeria and of Glyplie, which are parasitic on a Microgaster, whicli in turn preys upon the Army -worm, Leucania unipuncta ; and Chalcis albifrons Walsli, was bred from the cocoons of Pezomachus, an Ichneumon parasite of the same caterpillar. The pupse of some species are said to have the limbs and wings soldered together as in Lepidoptera, and the larvae sel- dom spin a silken compact cocoon. We have probably in this country at least a thousand species of these small parasites, nearly twelve hundred having been named and described in •Europe alone. They are generally large enough to be pinned or stuck upon cards or mica ; some individuals should be preserved in this way, others, as wet specimens. Fig. 136. Chalcis is known by the abdomen having a long pedicel, its much thickened, oval thighs, and curved tibiae. Chalcis bra- cata (Fig. 136), so named by Mr. Sanborn "in allusion to the ornamental and trousered appearance of the posterior feet" is about .32 inch in length. "Reaumur has described and figured a species of Chalcis, which is parasitic in the nest of the American wasp Epipone nitidulans and which he regarded as the female of that wasp." (Westwood.) The genus Leucospis is of large size. It is known by having the large ovipositor laid upon the upper surface of the abdo- men, and being spotted and banded with yellow, resembling wasps. One of our more common species is the L. affinis (Fig. 137) of Say. The Cuban L. Poeyi Gueriu is para- sitic on the Megachile Poeyi of Guerin. The well-known Joint-worm, Eurytoma, Fig. 137. ^or Isosoma Walsh) produces galls on wheat- stems. The antennae are, in the male, slender and provided with verticils of hairs. The acutely oval abdomen has a short pedicel. The hind legs are scarcely thicker than the fore limbs. E. hordei Harris (Fig. 138) is found in gall-like swellings of wheat-stalks. It is still a matter of discussion, 204 HYMENOPTERA. whether it du-ectlj' produces the galls, or is parasitic, like many of the famil}-, on other gall-insects. Dr. Harris, who has studied the habits of the Joint-worm, states that the body of the adult fl}^ is jet black, and that the thighs, shanks (tibiae), and claw-joints, are blackish, while the knees and other joints of the feet, are pale-yellow. The females are .13 inch long, while the males arc smaller, have a club-shaped abdomen, and the joints of the antennae surrounded with a A'crticil of hairs. The larva is described by Harris from specimens received from Virginia, as varying from one-tenth to nearly three-twentieths of an inch in length. It is of a pale 3'ellowish white color, Avilh an internal dusky streak, and is destitute of hairs. The head is round and partially retractile, with a distinct pair of jaws, and can be distinguished from the larvjB of the dipterous gall-flies by not having the v-shaped organs on the segment succeeding the head. During the sum- mer, according to Mr. Gourgas's observa- tions reported by Dr. Harris, and when the barley or wheat is about eight or ten inches high, the presence of the young Joint-worms is detected "b^^ a sudden Fi£?. 138. check in the growth of the plants, and the yellow color of their leaves," and several irregular gall- like swellings between the second and third joints, or, accord- ing to Dr. Fitch, "immediately above the lower joint in the sheathing base of the leaf;" or, as Harris states, in the joint itself. The ravages of this insect have been noticed in Avheat and barley. During November, in New England, the worms transform into the pupa state, according to the observations of Dr. A. Nichols, and "live through the winter unchanged in the straw, many of them in the stubble in the field, while others are carried awaj'^ when the grain is harvested." In Virginia, however, the larva does not transform initil late in February, or early in March, according to Mr. Glover. From early in May, until the first week in July, the four-winged flies issue from the galls in the dry stubble, and are supposed to im- mediately la}^ their eggs in the stalks of the young Avhcat or barley plants. The losses by this insect has amounted, in Virginia, to over a third of the whole crop. The best remedy CHALCIDIDvE. 205 against the attacks of this insidious foe, is to burn the stubble in the autumn or spring for several successive j-ears. Plough- ing in the stubble does not injure the insects, as they can work their way out of the earth. It has been objected by Westwood, Ratzburg, and more recently by Mr. Walsh, (who afterwards changed his views), that as all the species of this family, so far as known, are para- sitic, the Eurytoma cannot be a gall-producer, and that the galls are made by a dipterous insect (Cecidomyia) on which the Eurytoma is a parasite ; but, as they offer no new facts to support this opinion, we are inclined to believe from the statements of Harris, Fitch, Cabell, T. Glover (Patent Office Report for 1854), and others, that the larva of the Eurytoma produces the gall. We must remember that the habits of comparatively few species of this immense family have been studied ; that the genus Eurytoma is not remotely allied to the C3aiipidse, or true gall-flies (which also comprise animal parasites), in which group it has actually been placed by Esen- beck, for the reason that in Europe "several species of Eurytoma have been observed to be attached to differenlj kinds of galls." (Westwood.) Dr. Fitch also describes the Yellovz-legged Barley-fly, Eim/toma fl(W/pes, Avhich produces similar galls in barlc}', and differs from the Wheat Joint-worm in having yellow legs, while the antcnn;ii3 of the male arc not surrounded with whorls of hair. The Eurytoma secalis Fitch infests rj^e. It differs from E. hordei in "having the hind pair of shanks dull pale-yellow, as well as the forvrard ones." We shall also see beyond that several species of Saw-flies produce true galls, while other species of the same genus are external feeders, which reconciles us more easily to the theory that the Eurytoma hordei, and the other species described by Dr. Fitch, differ in their habits from others of the family, and are not ani- mal parasites. Indeed the Joint-worm is preyed upon by two Chalcid parasites, for HaiTis records flnding the larvae, proba- bly of Torymus, feeding on the Eurytoma larvae, and that a species of Torymus (named T. Harrisii, by Dr. Fitch, and per- haps the adult of the first-named Torymus) and a species of Pteromalus arc parasites on Eurytoma. In Monodontomerus (Toryinus) the third joint of the an- 206 HTMENOPTERA. tennse is minute, and the hind femora are thick, but not ser- rated, and beneath armed with a tooth near the tip. The wings are rudimentary so that it does not quit the cell. Newport states that the larva is flat, very hairy, and spins a silken cocoon when about to pupate. It is an "external feed- ing parasite" consuming the pupa as well as the larva of An- thophorabia. The imago appears about the last of June, perforating the cell of the bee. It also lives in the nests of Osmia, Anthophora, and Odynerus. The genus AnthojjJior'abia is so-called from being a parasite on Anthophora. The males differ remarkably from the females, especially in having simple instead of compound eyes, besides the usual three ocelli. A. megachilis Pack. (Plate 3 ; fig. 7, larva ; 7 a, pupa) is a parasite on a species of Megachile. The larva is white, short and thick, cylindrical, with both extremities much alike ; the segments are slightly convex, and the terminal ring is orbicular and rather large. Length, .04 inch, being one-third as broad as long. On opening the cells of Megachile, Ave found nearly a dozen containing these para- sites, of Avhich 150 larvae Avere counted clustering on the out- side of a dead and dr}'^ Megachile larva. In England they occur, according to Newport's observations, in much less num- bers, as he found from thirty to fifty in a cell of Anthophora. A few females hatched out in the middle of October, and there were a few pupae loft, but the majority Avintcred OA'er in the larva state, and a ncAV and larger brood appeared in the spring. Perilamp^is is a beautiful genus, with its shining, metallic tints. The eleven-jointed antennae are short, lying when at rest in a deep frontal furrow. The head is large, Avhile the abdomen is slightly pedicelled, being short, contracted, Avith the ovipositor concealed. P. pJatygaoter Say and P. triavgu- laris Say Avere described from Indiana. The numerous species of Pteromalus often oviposit in the larviie of butterflies. In this genus the antennae are inserted in the middle of the front. The abdomen is nearly sessile, ob- tusely triangular, or acutely ovate in form, Avith the ovipositor concealed. The femora are slender. There are about three hundred species known to inhabit Europe. Pleromalus va- nessce Harris is a parasite on Vanessa Antiopa. P. disio- CHALCIDID^. 207 Fis:. l.)9. camp^ Harris infests Clisiocampa. ^^ Pteromalus apum is parasitic m the nests of the Mason-bee." (Westwood.) A spe- cies of this or an allied genus (Fig. 139) infests the eggs of the Clisiocampa Ameri- cana. Its eggs are probably laid within those of the Tent-caterpillar moth early in the summer, hatching out in the autumn, and late in the spring or early in June. An allied genus, Siphonura, is a para- site on galls. It resembles a beetle, Mor- della, from its very peculiar scutum. The antennae of Semiotellus are twelve-jointed. S (Ceraph ron) destructor Say (Fig. 140), according to that autoor, destroys the Hessian-fly, while lying in the "flax-seed" state. Fitch de- scribes it as being a tenth of an inch long, black, with a brassy green reflection on the head and thorax, while the legs and base of the abdomen are yellowish. In Encyrtus, which comprises over a hundred species already known, usually rather small in size, the body is short and rounded, ihe eleven-jointed antennae are inserted near the mouth The thorax is square behind, and the sessile abdomen is short and broad at the base. Encyrtus Bolus and E. Recite are described from North America by Mr. F. Walker. Encyrtus varicorm's is in Euroi)e found as a parasite in the cells of Eumenes coarctata. The antennae of Eidoj)Jius are nine- jointed, with a long branch attached to the thi'S,'fonrth, and Wfch joints. The abdomen is flattened, sessile. E. hasalis Say was described from Indiana. We figure a Chalcid (Fig 141, ^;^), allied to Eulopus, which preys upon the American Tent Caterpillar. _ A species of Blastophoga (B. grossorum Grav.) is interest- ing as It IS the means of assisting in the fertilization of the Fig Fiff. 110. Fi- 141. 208 HYMENOPTERA. blossoms, which act, as applied to this instance of the fertiliza- tion of flowering plants b}^ insects, has been called by Mr. Westwood " caprilication." Cynipid^ Westwood. (Diploleparice Latreillo.) Gall-flies. In this most interesting family we have a singnlar combination of zoological and biological characters. The gall-flies are closely allied to the parasitic Chalcids, bnt in their habits are plant- parasites, as thc}^ live in a gall or tnmor formed by the ab- normal grovrth of the A'egetable colls, duo to the irritation first excited v/hou the egg is laid in the bark, or substance of the loaf, as the case may be. The generation of the summer broods is :ilso anomalous, but the parthenogenesis that occurs in those forms, by which immense innnbers of females are produced, is necessary for the work they perform in the economy of nature. When v>-c seo a single oak hung with countless galls, the work of a single species, and learn how numerous are its natural V. Jir. enemies, it becomes evident that the demand for a great nu- merical increase must be met by extraordinary means, like the generation of the summer broods of the Plant-lice. The gall-flies are readily recognized by their resemblance to certain Chalcids, but the abdomen is much compressed, and tinually very short, while the second, or the second and third seg- ments, arc greatly developed, the remaining ones being imbri- cated or covered one by the other, leaving the hind edges exposed. Concealed within these, is the long, partially coiled, very slender ovipositor, which arises near the base of the abdo- men.* Among other distinguishing characters, are the straight *rig. 142. I, nbtlomcn of Cijnip.t quercus-aciculnta Osten Saoken, with the ovipos- itor cxsertpd ; II, the same with the ovipositor i-etraeted; III, the abdomen of the female of Figites (Diplolepis) Mineatus Say; IV, the same showing the ventral portion, in nature covered f).v tlic tcr^jal portion of the abdomen ; V, end view of the CYNIPID^. 209 (not being elbowed) thirteen to sixteen-jointed antennae, the labial palpi being from two to four-jointed, and the maxil- lary palpi from four to six-jointed. The maxillary lobes are broad and membranous, while the ligula is fleshy, and either rounded or square at the end. There is a complete costal cell, while the subcostal cells are incomplete. The egg is of large size, and increases in size as the embryo becomes more devel- oped. The larva is a short, thick, fleshy, footless grub, with the segments of the body rather convex. When hatched they immediately attack the interior of the gall, which has already formed around them. Many species transform within the gall, while others enter the earth and there become pupae. It is well known that of many gall-flies the males have never been discovered. "Ilartig says that he examined at least 15,000 specimens of the genus Cynips, as limited l>y him, with- out ever discovering a male. To the same purpose he collected about 28,000 galls of C>/mps divisa, and reared 9,000 to 10,000 Cynips from them ; all were females. Of C. folii, likewise, he had thousands of specimens of the female sex without a single male." (Osten Sackcu.) Siebold supposes in such cases that there is a true parthenogenesis, which accounts for the immense number of females. Mr. B. D. Walsh has discovered (American Entomologist, ii, p. 330) that C;/iiips querciis-acicukUa O. Sack., which pro- duces a large gall in the autumn upon the black oak, in the spring of the year succeeding lays eggs which produce galls disclosing C'jnips quercus-spongijica O. Sack. He proved this by colonizing certain trees with a number of individuals of C. qwercus-acicidata, and finding the next spring that the eggs laid by them produced C quercus-spongifica. The autumn brood of Cynips consists entirely of agamous females, while the vernal brood consists of both males and females, a:id Mi-. Walsh declares after several experiments that " the agamous autumnal female form of this Cynips (C, q. aclcalata) sooner or later reproduces the bisexual vernal forin, and is thus "a mere dimorphous female form" of O. q. sponglfica, abdomen of Cynips, sho\vin,!r the relations of segments 7-8, the sternal portion of the ciihth segment hein? obsolete; .fp, the single pair of abdominal spiracles ; VI, terminal ventral piece, from which the sheaths (s .s) and the ovipositor {<,) take their origin : it is strongly attached at m to the tergites of the sixth and seventh rings; o, ovipositor; s, s its sheaths; a, an appendage to r, the terminal stcrnite. — From Walsh. 14. 210 IITMENOPTERA. In this connection he refers to the discovery of Clans, in 1867, of several males of Psyche helix, -which had been snp- posed to be parthenogenons, thousands of specimens having been bred by Siebold, all of which were females. Baron Osten Sacken (in the Proceedings of the Entomol- ogical Society of Philadelphia, vol. 1, p. 50) sa3S that "a strong proof in confirmation of my assertion is, that in those genera, the males of Avhich are known, both sexes are obtained from galls in almost equal numbers ; even the males, not unfrequently, predominate in number (see Hartig, 1. c. iv, 399). Now the gall-flies, reared by me from the oak-apple, were all females. Dr. Fitch, also, had only females ; and Mr. B. D. Walsh, at Rock Island, Illinois, reared (from oak-apples of a different kind) from thirty-live to forty females, without a single male. This leads to the conclusion that the Cynipes of the oak-apples belong to the genera hitherto supposed to be agamons." For an account of the habits and many other interesting points in the biolog}"^ of these interesting insects, Ave further quote Baron Osten Sacken. ' ' Most of the gall-flies alwaj's attack the came kind of oak; thus, the gall of C. seminator Han-is. is ahvays found on the white oalc ; C. tubicola Osten Sacken on the poGt oak, etc. Still, some galls of the same form occur on different oaks ; a gall closely resembling that of C. quercus- glohulus Fitch, of the white oak, occurs also ou the post oak, and the swamp chestnut oak ; a gall Aery similar to the com- mon oak-apple of the red oak occurs on the bhick-jLack oak, etc. Are such galls identical, that is, are they produced by a gall-fly of the same kind? I have not been able to investigate this question sufficiently. Again, if the same gall-fly attacks dif- ferent oaks, may it not, in some cases, produce a slightly differ- ent gall ? It Avill be seen below, that C. quercus-futilis, from a. leaf-gall on the Avhite oak, is A'cry like C. qxtercns-papiUata from a leaf-gall on the swamp-chestnut oak. I could not perceive any diuerence, except a very slight one in the coloring of the feet. Both gall-flies may belong to the same species, and although the galls are somcAvhat different, they are in some respects analogous, and might be the produce of the same gall- fly on two difierent trees. CYNIPID^. 211 "Some gall-flies appear very early in the season; Cynips quercus-palustris for instance, emerges from its gall before the end of May ; these galls arc the earliest of the season ; they grow out of the buds and appear full grown before the leaves are developed. May not this gall-fly have a second generation, and if it has, may not the gall of this second generation be different from the first produced, as it would be under different circuuistances, in a more advanced season, perhaps on leaves instead of buds, etc? " A remarkable fact is the extreme resemblance of some of the parasitical gall-flies with the true gall-fly of the same gall. Thus, Cynips quercits-futilis, O. Sacken, is strikingly like Aulax? futilis, the parasite of its gall. The common gall on the black- berry stems produces two gall-flies which can hardly be told apart at first glance, although they belong to different genera." (Proceedings of the Entomological Society of Philadelphia.) Hartig has divided this family into tlu'ee sections : First, Cjaiips and its allies, the true gall-flies (Psenides) in which the second (counting the slender pedicel as the first) segment of the abdomen is longer than half its length, and the subcostal area is narrow, the basal areolet (cell) being opposite the base of the former. Cynips cojiflnens Harris forms the oak-apple commonly met with on the scrub-oak. There is a spring and summer brood. These galls, sometimes two inches in diameter, are green and pulpy at first, but when ripe have a hard shell with a spongy interior, in the centre of v/hich, lodged in a woody kernel, which serves as a cocoon, the larva transforms, escaping through a hole, which it gnaws through both the kernel and shell. We have found the fly ready to escape in June, and Dr. Harris has found it in October. Two galls are represented on Plate 4, fig. 13 ; the larger of which has been tenanted, after the gall-flies had escaped, by an Odynerus. Cynij^s gaUce-tinc- torioi Olivier produces the galls of commerce, brought from Asia Minor. Biorhiza (Apophyllus Hartig) is a wingless genus, and lives beneath the earth in galls formed at the roots of oak trees. Biorldza nigra Fitch is black throughout, including the antennae and feet, and is but .08 inch long. 212 HYMENOPTERA. Galls are often found on the blackberry, tenanted by another genus, Diasti-ophus, which has usually fifteen-jointed antennae in the male, and one joint less in the female. On opening a gall containing this fl}', we often find an inquiline gall-fly, Aulax, "showing the most striking resemblance in size, color- ing and sculpture, to the Diastrophus, their companion. The one is the very counterpart of the other, hardly showing any differences, except the strictly generic characters." (Osten Sacken.) These galls are also infested by Chalcid parasites, Callimome (two species), Ormyrus, and Eurytoma. Osten Sacken enumerates "eight C3'nipidous galls on the dif- ferent kinds of roses of this country." The flies all belong to the genus Rhodites^ which is distinguished by the under side of the last abdominal segment being drawn out into a long point, while the antenniB are fourteen-jointed in both sexes. R. toscb produces the bede- guar gall ("from the Hebrew hedcguacJi^ said to mean rose-apple"). It was formerlj' used as a medicine. The galls form a moss-like mass, encircling the rose branch. Rliodites dichlocerus of Harris (Fig. 143), produces hard, woody, irregular swellings of the branches. We now come to the second section, the Guest gall-flies (In- quiliuETe), which are unable to produce galls themselves, as they do not secrete the gall-producing poison, though possessing a well developed ovipositor. Hence, like the Nomada, etc., among bees, they are Cuckoo-flies, laying their eggs in galls already formed. This group may generally, according to Mr. Walsh, be dis- tinguished from the preceding by the sheaths of the ovipositor always projecting, more or less, beyond the "dorsal "\alvc," v/hicli is a small, hairy tubercle at the top of the seventh ab- dominal segment. This dorsal valve also projects greatly. In almost all the species, the ovipositor projects from between the tips of the sheaths. Among the Inquiline genera are Sifnophnis, A7nbIynotus, jSynerges, and Aulax, which are guests of various species of Cynipides. In Ftgites and allies (Figitidae) , the third section of the TENTHREDINID JE . 213 family, the second segment is shorter tlian half the length of the abdomen, being much longer and less high and compressed than in the Cynipides, and the ovipositor is retracted within the abdomen. These insects are true internal parasites, re- sembling the Chalcids. Ihalia is a parasite on a Avood-beetle. This genus has, by AValsh, been placed in the Cj-nipides. Figites has feather-like antenuiB in the male ; it is a parasite on the larvae of Sarcophaga. The genus AUotria is a para- site on Aphis. Walsh states that two genera, which he has identified as Kleidotoma and Eucoila are true Figitida', and "have the wings fringed like a Ilymar, and the former has them emargi- nate at tip with the radial area in my species distinctly open, and the latter simple at tip with the radial area in my species marginally closed by a coarse brown vein." Eucoila is sup- posed to be parasitic on some insect attacking the turnip. Tenthredinid^ Leach. The Saw-flies connect the Hymen- optera with the Lepidoptera. In the perfect state they eon- form to the Hymenop- , „ terous type, but as larvae they would often be mistaken for Lepi- dopterous larvae, and in their habits closely resemble many cater- pillars. The three divisions of the body, usually so trenchantly marked in the higher Hymenoptera, are here less distinct, since the abdomen is sessile, its basal ring being broad and applied closely to the thorax, while the succeeding rings are very equal in size. The head is broad and the thorax wide, closely resembling that of the Lepidoptera. The wings (Fig. 144, fore-wing) are larger in proportion to thd rest of the body than usual ; the^^ are more net- veined, the colls being more numerous and extending to the outer margin.* *In treating of this family we avail ourselves largely of the important work on the American species, publishing at the time of writing, by Mr. E. Norton, in the Transactions of the American Entomological Society, vols. 1, 2. We therefore 214 HYMENOPTERA. All these characters show that the saw-fly i^ a degradecl Hymenopter. The autennai are not elbowed ; are rather short and simple, clavate, but in rare instances fissured or feathered. The ab- domen consists, usually, of eight external segments, the two last being aborted on the under side, owing to the great develop- ment of the ovipositor. The ovipositor or "saw" (compare Fig. 24) consists of two lamelhc, the lower edge of wliich is toothed and fits in a groove in the under side of the upper one, which is toothed above, both protected l)y the usual sheath-like st^'lets. On pressing, saj's Lacaze-Duthiers, the end of the abdomen, we see the saw depressed, leave the direction of the axis of tlie body, and become perpendicular. By this movement the saw, which both cuts and pierces, makes a gash in the soft part of the leaf where it deposits its eggs. The eggs are laid more commonly near the ribs of the leaf, in a series of slits, each slit containing but a single egg. ''Some species, on the other hand, introduce their eggs by means of their saws into the edges of leaves (Nemaius covju- gatus Dahlb.), and others beneath the longitudinal ribs of the leaves. A few, indeed, merely fasten their eggs upon the outer surface of the leaves (Nc.iatuf; grossukmm, etc.), attaching them together like a string of beads (Reaumur, vol. v, plate 10, fig. 8), whilst a fev/ place them in a mass on the surface of the leaf (ibid, plate 11, figs. 8, 9)." (Westwood.) The irritation set up by the saws in the wounded leaf, causes a flow of sap vvhicli is stated by Westwood to be imbibed by the egg, so that it swells gradually to tv, ice its original size. It is known that the eggs of ants increase in size as the embryo develops, and we would copy his diagram (Fig. 114), showing the venation of the wing (comp.ire Fig. 29 and our nomenclature), with the explanation of parts given by liim. a, stigma; b, costa or costal margin; c, apical margin; rf, costal and post- costal veins; r, cxtcrnomedial ; /, ff, anal; 7(, posterior margin; i, marginal vein; j, submarginal vein; /.-, first, second, and third (transverse) submargiual nervurcs; I, recurrent nervures (discoidal); m, discoidal vein; n, first and second inner ai)i- cal or sul>marginal nervures. Bulte or clear spots, on the veins or nervures, with bullar or clear lines crossing them. 1,2, marginal or radial cells ; ;>, 4, 5, C, submar- ginal or cubital cells; 7, S, 9, discoidal cells; 10, costal cell; 11, 12, brachial or me- dial cells; 13, 14, inner and outer apical cells. (Hinder cells, Hartig. Cellule du limbe, St. Farg.) Ko. 11 is sometimes the medial, and Xos. 12 and 13 the submedial cells ; Nos. and 14 the apical cells ; Nos. 7 and 13 discoidal ; Nos. 10, 11, 12, 15, the first, second, third and fourth brachial cells; l.'i, lanceolate cell. 1, open; 2, con- tracted; 3, petiolate; 4, subcontracted; 5, with oblique cross nervure; G, with straight cross uei"vuro. TENTHREDINID^. 215 question whether the increase in size of the eggs of the Saw- fly is not rather due to the same cause. -The punctures in the plant often lead, in some genera, to tlie production of galls, in whicli the larvae live, thus showing tlie near relationsliip of this family to the gall-flies (Cynipidsc), The larvae strongly resemble caterpillars, but there are six to eight pairs of abdominal legs, whereas the caterpillar has but Ave pairs. Many species curl the hind body up spirally when f^edhig or at rest. They are usuallj^ green, with lines and markings of various colors. They usually moult four times, the last change being the most marked. Most of the larvae secrete silk and spin a tough cocoon, in which they hiber- nate in the larva, and often in the pupa state. The pupa has free limbs, as in the other families. The eggs are usuall}' de- posited in the leaves of plants, but in a few cases, according to Norton, iu slender or hollow stems. While some are slug- shaped, like the Pear-slug, others like Lyda inanUa, mentioned by Westwood, live on rose bushes, and construct a "portable case, formed of bits of rose-leaves arranged in a spiral coil ; " and other species are leaf-rollers, like the Tortricids. The larva of CejjJius does injury to gi'ain, in Euiope, by boring within the stems of wheat. A remarkable instance of the care of the saw-fl}^ for her young, is recorded by Mr. R. II. Lewis, who observed in Australia, the female of Perga Lewisii deposit its eggs in a slit next the midribs of an Eucalyptus leaf. They were placed transversely in a double series. "On this leaf the mother sits till the exclusion of the larA^ae ; and as soon as these are hatched, the parent follows them, sitting with out- stretched legs over her brood, protecting them from the attacks of parasites and other enemies Avith admirable perseverance." (Westwood.) The species are mostly limited to the temperate zone, but few being found in the tropics. The perfect insects mostly occur in the early summer, and are found on the leaves of the trees they infest, or feeding on flowers, especially those of the umbelliferous plants. The genus Cimbex contains oin* largest species, the antennae ending in a knob. C. Americana Leach is widely distributed, and variLvj greatly in color. The large whitish larva, with a 216 IIYMENOPTERA. blackish dorsal stripe, may be found rolled up in a spiral on the loaves of the ehn, birch, linden and willow trees. When disturbed it ejects a fluid from pores situated above the spira- cles. It constructs a large tough parchment-like cocoon, and the fly appears in the early summer. The genus Tricliiosoma is recognized by its hairy body, and the autennte have five joints preceding the three-jointed club. T. iriavf/uh(m Kirby is found in British America and Colorado, and a variety, T. bicolor Harris, on Mount Washington ; it is black, except the tip of the abdomen, with the fourth and fifth joints of the antennas piceous, and the thorax is covered with ash-colored hair. In Abin the antennae are seven-jointed, with the club obtuse ; the body is villose, the abdomen having a metallic silken hue. The Abia caprifolii Norton (Fig. 145, larva) is very destruc- tive to the Tartarian Honeysuckle, sometimes stripping the; bush of its leaves during successive sea- sons in Maine and Massachusetts. It hatches out and begins its ravages very soon after the leaves are out, eating cir- cular holes in them. It lies curled up on the leaf and when disturbed emits drops of a watery fluid from the pores in the sides of the body, and then falls to the ground. During the earlj' part of August it spins a pale yellowish silken cocoon, but does not change to a pupa. Mr. Riley states, until the following spring. He describes the larva as being common about Chicago ; that it is "bluish green on the back, and yellow on the sides, which are pale near the spiracles, and covered with small black dots. Between every segment is a small, transverse, yellow band, with a black spot in the middle and at each end. Head free, of a brownish black above and color of the body beneath." The fly is described by Norton as being black, with faint greenish reflections on the abdomen ; there are two white bands at the base of the metathorax, and the wings are banded. It is .30 inch long and the wings ex- pand .70 inch. The larvae can easily be destroyed from their Fig. 115. TENTHREDINID^. 217 habit of falling to the ground when the bush is shaken, where they can be crushed by the foot. Dr. Fitch has reared AMa cerasi from one or two cocoons found on the wild cherry, the fly appearing in New York diunng March. Hylotoma is a much smaller genus ; the basal joint of the antenna is oval, while the second is small and round, and the terminal joint is very long. The larva is twenty-footed, and when eating curves the end of the body into the form of an S. The pupa is protected by a gauzy, doubly enveloping cocoon. H. 3IcLeayi Leach is wholly black, sometimes with a tisige of blue. It is found throughout the Northern States. The genus PristipJiora, closely allied to Nematus, is known by its nine-jointed antenntB, and the single costal cell ; the first submarginal (subcostal) cell ha^'ing two recurrent veinlets. P. identidem Norton has been discovered by Mr. W. C. Fish to be destructive to the cranbeny on Cape Cod. He has reared the insect, and sent me the following notes on its habits, while the adult lly has been identified by Mr. Norton, to whom I submitted specimens. The larvjie were detected in the first week of June, eating the leaves ; "they were light or pale yel- lowish green when first hatched," and grew darker with age. The head of the young was dark, but in the full-grown worm lighter. When full-grown they were about .30 of an inch in length, and had two lighter whitish green stripes running along the back from head to tail. They had spun their cocoons by the 20th of June in the rubbish at the bottom of the rearing bot- tles. On the 29th of June the}^ came out in the perfect state. We would add to this description that the body, in two alco- holic specimens of the larvae, was long, cylindrical, and smooth, with seven pairs of abdominal feet. The head is full, rounded and blackish, but after the last moult pale honey-yellow. The male is shining black, and Mr. Norton informs me that it is his P. idiota. P. grossidarioi Walsh is a widely diffused species in the Northern and Western States, and injures the currant and gooseberry. The female fly is shining black, while the head is dull j-ellow, and the legs are honey-yellow, with the tips of the six tarsi, and sometimes the extreme tips of the hinder tibia; and of the tarsal joints pale dusky for a quarter of their length. The wings are partiall}^ h3^aline, with black veins, a 218 HYMENOPTERA. honey-yellow costa, and a dnsky stigma, edged with honey- yellow. The male differs a little in having black eoxve. • Mr. Walsli states that the larva is a pale grass-green woi'm, half an inch long, with a ])lack head, which becomes green after the last monlt, bnt with a lateral brown stripe meeting with the opposite one on the top of the head, where it is more or less confluent ; and a central brown-black spot on its face. It appears the last of June and early in July, and a second brood in August. They spin their cocoons on the bushes on which they feed, and the fly appears in two or three weeks, the specimens reared by him flying on the 26th of August. P. »ycophanta Walsh is an "inquiline," or guest gall-saw-fly, inhabiting a Cecidomyian gall on a willow. The genus Euura comprises several gall-making species. It diflfers from the preceding genus in the second, instead of the first, subniarginal cell having two recurrent venules. Mr. Walsh has raised E. orbitaUs Norton (E. genuina Walsh) from galls found on Salix humilis. This gall is a bud which is found enlarged two or three times its natural size, before it unfolds in spring. The larva is twenty-footed, is from .13 to .19 of an inch long, of a greenish white color, and the head is dusky. It bores out of its gall in autumn, descending an inch into the ground, where it spins a thin, silken, whitish cocoon. The gall of E. salicis-ovum Walsh is found on Salix cordata. The female is shining yellow, while the ground color of the male is greenish white. The gall of this species is an oval roundish, sessile, one-chambered, green or brownish swell- ing, .30 to .50 of an inch long, placed lengthwise on the side of small twigs. The larva is pale yellowish, and the fly appears in April. The fly is, according to Walsh, " absolutely undistin- ffuishable by any reliable character from the guest gall-saw-fly, Euura ijerturhans Walsh," which inhabits dipterous galls made by Cecidomyian flies on the willow and grape (Walsh). If these two "species" do not differ from each other, either in the larva or adult state, "by any reliable characters," then one must question whether the variation in habits is sufficient to sej^arate them as species, and whether E. Galici.>o'\'um does not, some- times, instead of forming a new f!;nll, lay ito eggs in a gall readj^- nuule by a dipteroiia galMly. V.'e have cecn that Odyncrus TENTHKEDINID^. 21& albophaleratus, which usually makes a mud cell situated in the most diverse places, iu one case at least, makes no cell at all, but uses the tunnel bored out by a Ceratina ! and yet we should not split this species into twQ, on account of this difference in its habits. We had writteil ^is before meeting with Mr. Norton's remark that "it is difficult to give a hearty assent to Mr. Walsh's inquilines or guest-flies, without further inves- tigation." (Transactions of the American Entomological Society, vol. i, p. 194.) In Nematus the nine-jointed antennre have the third joint longest. There is one costal and four subcostal cells, the second cell receiving two recurrent vcinlets ; the basal half of the lanceolate cell is closed ; the hind wings have two mid- dle cells, and the tibiiie are simple. The larvae are hairy with warts behind the abdominal feet. The}' have twenty feet, the fourth and eleventh segments (count- ing the head as one) being footless. They are either solitary, feeding upon the leaves of plants, or social and generally found on pine trees, while some species live in the galls of plants. The pupa, according to Ilartig, is enclosed in an egg-shaped cocoon, like that of Lophyrus, but less firm, though with more outside silk. It is generally made in the earth, or iu leaves which fall to the ground. N. vertebratus Say is green, with the antennaa and dorsal spots blackish, the thorax being trilineatc. There are fifty species in this countr}^, of which the most injurious one, the Gooseberry saw-fly, has been brought from Europe. This is the N. ventricosus King which was undoubtedly imported into this country about the year 18G0, spreading mostly from Rochester, N. Y., where there are extensive nurseries. It does more injury to the currant and gooseberry than any other native insect, except the currant moth (Abraxas ribearia). Professor Winchell, who has studied this insect in Ann Arbor, Michigan, where it has been very