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Show 400 INSECTA. in this respect to the former. They are all furnished with wings, and their gait is he~vy · . . The body of the larvre ts long, a~m.ost se~Incyhndrical, soft, frequently rugos-e, whitisl~, and ~1V1ded ~nto twelve annuli, with six squamous feet; the head ts squamous and armed with stout mandibles. Each side of the body is furnished with nine stigmata; its posterior extremity is thicker, rounded and almost always doubled under it, so that the back being arcu· ated or convex, the animal cannot extend itself in a straight line crawls badly on a level surface, and falls backwards or on i~s side at every instant. An idea of their form may be obtained from that of the larva, so well known to gardeners by the name of ver blanc, which is that of the Melolontha vulgaris(l ). , Some of them require three or four years to become pupre; they construct in their place of residence an ovoid shell, or one resembling an elongated ball, composed of earth or the debris of substances they have gnawed, the particles of which are cemented by a glutinous matte~ produced from their body. Their aliment consists of the dung of various animals, mould, tan, and roots of vegetables, frequently such as are necessary to man, of which they sometimes destroy immense quantities, to the great loss of the cultivator of the soil. The trachere of these larvre are elastic, while those of the perfect Insect are tubular. There is also a remarkable difference in the nervous system in these two states. The ganglions are less numerous and more closely approximated in the perfect Insect, and the two posterior ones give off numerous radiating filaments. According to the observations of M. Marcel de Serres on the eyes of Insects, those of most of t?e Lamell~· cornes present peculiar characters, which approXI!flate their organization. to that of the Tenebrionites, Blattre, and other lucifugant Insects. The alimentary canal is generally very long, particularly (1) Our common grub8, which are so abundant in dung-hills, gardens, &c., art larvz of various species of Lamellicornes. .11m. Ed. COLEOPTERA. 401 in the Coprophagi, and contorted ronnd itself; the chylific ventricle is studded with papillre, which M. Dufour has ascertained to be bursre, intended for retaining the alimentary fluid. The biliary vessels in number, and the manner of their insertion, resemble thQSe of the carnivorous Coleoptera, but' are much longer and more slender. We will divide this family into two tribes( I). In the first or that of the ScARABlEIDEs, we find the antennre terminating in a foliaceous and generally plicatile club, and composed in others of joints that fit into each other, either in the form of a reversed cone or nearly globular. The mandibles are identical or almost similar in both sexes, but the head and thorax of the males exhibit peculiar projections or eminences; sometimes also their antennre are more developed. This tribe(2) corresponds with the genus ScA'RABJEus, Lin. The alimentary canal is generally much longer than that of the Lamellicornes of the following tribe Ol' the Lucanides, and the resophagus isproportionallymuch shorter. The adipose tis5ue, or the epiploon, is generally almost reduced to nothing, whilst here it is well ma1·ked. But it is chiefly by the genital apparatus of the males that the Scarabreidcs are distinguished, not only from the latter, but also from all other Pentamera. Their testes, according to the observations of M. Dufour, consist of spe1·matic capsules-tufts according to M. Cuvier-which are tolerably large, very distinct and pediculated; the number varies according to the genus. The larvre-Cuv., Rcgn. Anim.-have a cylindrical stomach surrounded by three ranges of little creca, a very sho1·t small intestine, an extJ·emcly thick, turgid colon, and a moderate rectum. We will divide this genus into SC\'CI'al small sections established on characters drawn from the organs of manclucation, antennre, and {1) The anatomy is so different, according toM. Dufour, that these two tribes should constitute as many families. The section!! ,,.ould then hecome tribes and some of their divisions so many p1·incipal genera-Copris, .flplwditts, Grotrupe8, Scarabreus, Rutcla, Melolonflta, Glapkyrus, and Ceton£a for the first tt·ibe . . (2) In thus retaining the pt·imitive c.·tcnt of this division, we have acted in con· formitywith out• first edition; we still think, however, that althoug·h we may reject several of the genera established in modern times, there aJ·e some that must he received; such in geneJ·al arc those ot T·'alwicius. VoT .. III.-3 A |
