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Show SO INSECTA. . are always largest, lips; but these wings, of which the suphe:I~ europtera, and are have fewer nervures than those of t 1 • terminated by an not veined; the abdomen of the fema es IS ovipositor or sting. 11 provided with Besides the.i r compoun d eyes they are a ry not only ac- three small s.i mple ones. Th e.t r. antennre vao f 't he same spe-b t ven m the sexes cording to the genns, u e :fil'" m or setaceous. The cies; general1 y , h owever, they are I !lOr longated, and fixed b. ually narrow, e . maxillre and la mm are us les(l) form a sem1- . h l d by long muse ' in a deep cavtty oft e lea fi ld d p at their extremity, tube inferiorly, are frequently 0 ~ .u of nutritious fluids and better adap~ed f~r the t::~~~~s~:r~ a proboscis. The than for masticatiOn; ~~sever. d ~at its extremity, or long ligula is membranous, etther Wl en~t nterior base, and being . h · th pharynx at 1 s a and fihform, avmg e of sub-labrum or epipharynx. frequently covered b~ a sort maxillary and two labial. The They have four pal pi, two f hi.ch the anterior .t d segments o w thorax consists of three um e .c' d din one(2). The d h two last are contoun e is very short an t e h b d The abdomen is wings are laid horizontaii~ 01 : ;it~e t~:C~d or pedicle to the most commonly s.uspendedhy , The tarsi consist of five · t mity of the t 01 ax. . pos.t eriO. r. ex re f them be.m g d' . d d The ovipositor 1 v1 e · entire JOints, none 0 d f three long and slender and sting(3) are generally compose o (1) The mentum, here, parb.c t. pates .m t h'I S g eneral motion, while in the other · · fi d and immovable. · triturating Insects tt IS xe 11 d is ver short, forms but a simple superl~r (2) The metathorax, properly so ca e ' y t of the abdomen, so that m · d "th the first segmen hoop, and is intimately mute WI • d of four segments, the second · d from above, IS compose truth, the thorax, vtewe . b the latter pl•esents two very and last of which are the largest; m a ~eatdt~uml teerd, its second segment, always . Wh the abdomen IS pe tcu a ' distinct stigmata. . en t b 1 n to it is apparently the first. supposing the precedmg one o e o g 1 'F the middle of the posterior and (3) Both are formed on the same mode . rom} . each composed of two . f h bd en proceed two ammre, , f inferior extremtty o t e a om '. h th and sometimes in the form o a Pieces, sometimes valvular and servmg as a s eha , . n"tted in one which com· . th re two ot er pteces u ' stylet or of palpl· Between em a l' t' the superior receives the P . . t' When they lorm a s mg, . ose the ovtposltor or s mg. h d" t the ovipositor consists . . 1 In the Tent re me ce, th other in an mferlOr cana or groove. . r d ne against the other by e f two pieces resembling blades of kmves, app te o . :ide; they are' striated transyersely, and dentated along the margm. . HYMENOPTERA. 81 pieces, two of which serve as a sheath to the third in those which are provided with an ovipositor, and one alone, the superior, has a groove underneath for lodging the two others. In those where this ovipositor is transformed into a sting, this offensive weapon and the oviduct are serrated at the extremity. M. J urine has discovered good auxiliary characters for the distinction of genera, in the articulation of the wings( I); to describe them, however, would not be in unison with the nature of this work, and ceuld not remove the necessity of .. referring to his. We will merely observe that he chiefly employs those resulting from the presence or absence, number, form and connexion of two sorts of cel1s situated near the external margin of the ·superior wings, which he styles radial and cubital. The middle of this margin most commonly presents a little caJlosity ca1led the wrist or carpus. From the latter arises a nervure, which running towards the extremity of the wing, forms, in conjunction v;ith this margin, the cell named radial, that is sometimes divided into two. Near this spot at•ises a second nervure, which also proceeds to the posterior margin, leaving a space between it and the preceding one-this space is that of the cubital cells, the number of which varies from one to four(2). The Hymenoptera undergo a complete metamorphosis. Most of their larvre resemble worms and are destitute of feet; such, for .instance, are those of our second and following families. Those of the first have six hooked feet, and frequently from twelve to sixteen others that are simply membranous. These latter have been named pseudo-caterpillars. Both kinds have a squamous head provided with mandibles, max- (1) Nouv. Meth. de class. les Hymen. et les Dipt. (2) See Encyc. Method., article Radiale, where this method is well described and pe1fectcd. Jurine has also published an excellent work on the organization of the wings in the Hymenoptera, in the Mem. Ac. Sc. Tur. We are also indebted to M. Chabrier, for his researches on this matter; they are, however, more general in their application. They are inserted in the Mem. du Mus. d'Hist. Nat. • VoL. IV.-L |