138 CLASS INSECTA. 



composed of a scaly stem, at the extremity of which is an 

 articulation equally scaly, and surmounted by a piece in 

 which are implanted transversely some small corneous parts, 

 which are trenchant, and may be considered as so many 

 teeth. The back of each mandible is, moreover, emboxed 

 externally in a scaly capsule, which is large, articulated at 

 its base, angular, and formed, as it were, of two levels, the 

 extremity of each of which is emarginated. 



The under lip, which M. Savigny considers as two pair 

 of jaws united, is divided by many sutures or imprinted 

 lines. Below and in the middle is seen a piece, the edges of 

 which are angular, above which two narrow pieces rise paral- 

 lely contiguous at their internal edge, and the extremity of 

 which is obtusely edged. On each side, in the direction of 

 the preceding, rises a scaly piece of the same figure as the 

 two middle ones, but larger, somewhat widened, and rounded 

 on the external side at the top. Towards its internal angle 

 are two tubercles, which might be taken for two palpi. The 

 general piece is flat, and resembles, being very slender, a 

 membranous leaf. 



The first two rings of the body do not form an entire 

 circle. They are open below. Also, the first two pair of 

 feet have a peculiar membranous support which fills the in- 

 tervals. These first two feet, and even the second, seem to 

 be attached immediately under the mouth, and are thus ana- 

 logous to the jaw-feet of the Crustacea. The first ring is 

 very open, and may be considered as a sort of corslet, being 

 plate-formed, and longer than each of the others. The third, 

 though nearly forming an entire round, is nevertheless open, 

 and has but a single pair of feet, inverted like the preced- 

 ing. The fourth segment is more closed, but has only a 

 single pair of feet. It is only at the fifth that the duplica- 

 tion of feet commences. Thus, supposing that the first seg- 

 ment, which may be considered the corslet, has no feet, the 



