CLASS INSECTA. 15 



this nomenclature, and making a general application of it, 

 we must wait until his researches, and the figures which are 

 to accompany them, shall be published. In practice, the de- 

 nominations already introduced may suffice. In relation to 

 this subject, justice as well as friendship compels us to call 

 the attention of naturalists to the labours of M. Chabrier, 

 ancient superior officer of artillery, respecting the flight of 

 insects. They form a part of the Memoirs of the Museum of 

 Natural History, and also constitute a separate work. The 

 figures are on a very large scale, like those of a memoir of 

 Jurine the Father, on the wings of the hymenoptera, a work 

 of the most patient research, as well as the preceding. 



As insects inhabit every where, they are provided with all 

 sorts of organs of motion, with wings and feet, which in 

 many species answer the purposes of fins and oars. The 

 wings are membranous, dry, and elastic pieces, usually trans- 

 parent, and attached to the sides of the back of the thorax. 

 The first, when there are four, or when there is but one 

 pair, are placed on the sides of the second segment, and the 

 second on those of the following, or of the metathorax. They 



des Sciences Naturelles," the denomiuation hypopteron, to that of parop- 

 tere. That of the enthorax will change also, under some circumstances, 

 and should be called entocephalon, (relative to the head) and entogaster (in 

 relation to the abdomen. He remarks that the head of insects is composed 

 of many segments. We have also observed that the bill of the cricket 

 representing the lower lip, is not attached to the head, but to the mem- 

 brane which unites it with the thorax. Thus, the two medullary chords 

 form underneath the mouth two contiguous ganglions. On this principle 

 let us consider the first segment of the body of the scolopendra, that 

 which supports the two hooks, as a division of the analogous head. It 

 appears that Knoch has distinguished the epimeros under the denomina- 

 tions of scajnilcB and parapleura, the hind chest by that of acetabulum, 

 •whilst the middle chest is the per istcethium. The first articulation of the 

 four posterior haunches forms, in most of the coleoptera, a transverse 

 lamina, articulated in the flank, and that is, as it appears to me, the piece, 

 he calls nicenum. 



