6 BRITISH LEPIDOPTERA. 



Trouvelot describes [American Naturalist, i., pp. 37-38) the exuvia- 

 tion of Telea polyphemus, and states that " the larva ceases to eat for 

 a day before moulting, spins some silk on the undersurface of a 

 leaf, secures the hooks of its hind-legs therein, and remains motion- 

 less. After a time, through the transparent skin of the neck, a second 

 head can be seen, larger than the first, belonging to the larva within. 

 A little before the actual moult takes place, the larva holds its body 

 erect, grasping the leaf with the two pairs of hind-legs only, the skin 

 being wrinkled and detached from the body by a fluid which circulates 

 between it and the worm ; two longitudinal bands are seen on each side, 

 produced by a portion of the lining of the spiracles which, at this 

 moment, have been partly detached ; meanwhile the contractions are 

 very energetic, and, by them, the skin is pulled off and pushed towards 

 the posterior part. The skin thus becomes so distended that it soon 

 tears just under the neck and then from the head. When this is 

 accomplished the most difficult operation is over, and the process of 

 moulting goes on very rapidly. By repeated contractions the skin is 

 folded towards the tail, like a glove when taken off, and the lining of 

 the spiracles comes out in long white filaments. "When about one- 

 half of the body has appeared, the head-shell still remains like a cap, 

 enclosing the jaws ; then the larva removes it by rubbing it on a leaf. 

 The larva finally crawls out of the skin which remains attached to the 

 silken pad made for the purpose. Once out of its old skin, the larva 

 feels with its head the aperture of every spiracle as well as the tail, 

 probably for the purpose of removing any fragment of skin which may 

 have remained in these delicate organs. Not only is the outer skin 

 cast off but also the lining of the air-tubes and intestines, together 

 with all the masticatory organs and other appendages of the head." 



The mode of ecdysis of Lyonetia clerckella appears to be somewhat 

 similar to that of the Nepticulids (vide, vol. i., p. 174), for Healy remarks 

 that on the skin splitting at the head, the larva gradually eats its way 

 forward, and as it feeds with the underside of its body facing the upper 

 surface of its food, the dark horny thoracic legs, as they successively 

 make their appearance out of the old skin, become very conspicuous. 

 The head of the larva is then very pale brown and has a dark brown 

 spot on each side. At length, after feeding for ten hours, the larva 

 entirely escapes from its old skin and remains motionless for some 

 time. The same observer describes (Ent. Mo. May., i., p. 19) the 

 moulting of Eriocrania unimaculella as not occupying five minutes. He 

 says that he observed the old skin to split on the front of the pro- 

 thorax, when the larva pressed its head against the side of its mine, 

 and then, by curving its body and violently jerking itself up and down, 

 drew its body out of the old skin. . . . The head was thrown off in 

 front and not permitted to recede down the body as the old skin had 

 done. The body was then quite white and spotless, but the dorsal 

 vessel slowly assumed a pale reddish tinge, the tip of the mouth 

 gradually became reddish-brown, whilst down the centre of its head, 

 two parallel pale brown lines appeared ; the head then became brown, 

 and shortly afterwards a dark triangular patch appeared on each side 

 thereof. The larva now resumed its feeding, the dorsal vessel 

 (? alimentary canal) became green, which gave a greenish tint to the 

 whole of the body. 



We have already stated that all those organs that have an ecto- 



