LEPIDOPTERA. 297 



pillar state. The moth comes forth about the middle of July. 

 The same insect, or one not to be distinguished from it while 

 a caterpillar, perforates the trunks of the red oak. Mr. New- 

 man * has recently given the name of Xyleutes, the carpenter, 

 to the genus including this insect, instead of Cossus, which it 

 formerly bore, because the latter, being the name of a species, 

 ought not to have been applied to a genus. The European 

 carpenter-moth, called Bombyx Cossusf by Linnaeus, will now be 

 the Xyleutes Cossus ; and our indigenous species will be the 

 Xyleutes Robinict, or locust-tree carpenter-moth. The moths 

 of this genus have thick and robust bodies, broad and thickly 

 veined wings, two very distinct feelers, and antennas, which are 

 furnished on the under-side, in both sexes, with a double set 

 of short teeth, rather longer in the male than in the female. 

 Their tongue is invisible. They give out a strong and peculiar 

 smell, whence they are sometimes called goat-moths by English 

 writers. 



Some caterpillars, which eat the leaves of plants, live in cases 

 or long oval cocoons, open at both ends, and large enough for 

 the insects to turn around within them, so as to go out of either 

 end. They do not entirely leave these cases, even when moving 

 from place to place, but cling to them on the inside with the legs 

 of the hinder part of their bodies, while their heads and fore-legs 

 are thrust out. Thus in moving they creep with their six fore- 

 legs only, and drag along their cases after them as they go. 

 These cases are made of silk within, and are covered on the out- 

 side with leaves, bits of straw, or little sticks. The caterpillars 

 are nearly cylindrical, generally soft and whitish, except the head 

 and upper part of the first three rings, which are brown and hard ; 

 they have sixteen legs ; the first three pairs are long, strong, and 

 armed with stout claws ; the others are very short, consisting 

 merely of slight wart-like elevations provided with numerous mi- 

 nute clinging hooks. When they are about to change their forms 

 their cases serve them instead of cocoons ; they fasten them by 

 silken threads to the plant on which they live, stop up the holes 



* See " Entomological Magazine," Vol. V. p. 129. 



t Subsequently named Cossus ligniperddby Fabricius. 



38 



