10 



BRITISH BUTTERFLIES. 



and by swallowing the chips he had made 

 duiing the operation. Indeed, this gastro- 

 nomic feat is often followed by a more exten- 

 S've performance of the same kind; for I have 

 often watched him devour the whole of bis 

 cradle, except a small shining circular patch 

 where it had been glued to the object on 

 which it was laid. No sooner, however, is 

 the cradle disposed of than he begins to feed 

 011 what we .should consider a more natural 

 and appropriate food, namely, the leaves of 

 trees and herbs a diet to which he confines 

 himself during the remainder of his caterpillar 

 existence. His exertions in the way of leaf 

 eating are truly wonderful, and many ento- 

 mologists have amused themselves and their 

 readers by calculating how many times its 

 own weight a caterpillar can consume in the 

 course of twenty-four hours a calculation 

 which tends greatly to the credit of the cal- 

 culator, but not much to advance the science 

 of natural history. 



A caterpillar's life is not, however, one of 

 continual feasting : he is subject to periodical 

 attacks of illness, three, four, five, or six in 

 number ; these arise from his body growing 

 too large for his skin, which, as a natural 

 coneequenee, grows too small and oppresses 

 him so much that it must be got rid of. The 

 caterpillar is perfectly aware of this, and 

 prepares in the most skilful and methodical 

 manner for the important event. He first 

 spins or weaves a little carpet on the surface 

 of the leaf or twig where he has been feeding, 

 and then fixes himself to this by means of a 

 circle of very small delicate hooks which sur- 

 round each of his claspers. The term claspers 

 T will presently explain. By means of these 

 hooks the caterpillar is able to cling so tightly 

 to the carpet he has prepared, that I believe 

 *'.t is quite impossible to remove him without 

 damaging both the carpet and the hooks ; in 

 lact, in the attempt to remove a caterpillar 

 when thus fixed, the life of the caterpillar is 

 often sacrificed. The process of moulting is 

 a very severe one ; and unless the caterpillar 

 be in a state of perfect health at the time it is 

 ol'rm fatal, and the poor creature is found 

 dead and still hanging by its claspers from its 



silken carpet. When the process of moulting 

 goes on favourably it may thus be described : 

 the fore part of the body is turned vigorously 

 from side to side, the skin of the second, 

 third, and fourth segments opens down the 

 back, and the head and anterior part of the 

 caterpillar protrude through the opening : 

 then immediately beneath the head may be 

 seen the shell-like covering of the old head, 

 split down the middle and often into three 

 pieces ; the caterpillar next, with a series of 

 convulsive struggles, creeps out of his old 

 skin, which is left attached to the carpet, and 

 is frequently so perfect and apparently so 

 plump that I have been completely deceived 

 into supposing that .he was still wearing his 

 old clothes. 



The head, antennae, jaws, and legs of the 

 caterpillar are persistent, and their horny 

 covering only is shed at the period of mo It ; 

 and Swammerdam tells us that not only the 

 horny covering of these parts and the skin of 

 the body comes away at each moult, but also 

 that "the throat and a part of the stomach, 

 and even the inward surface of the great gut, 

 change their skin at the same time. But this 

 is nob the whole of these wonders, for at the 

 same time some hundreds of pulmonary pipes 

 within the body cast also each its delicate and 

 tender skin. These several skins are after- 

 wards collected into eighteen thicker, and, as 

 it were, compounded ropes nine on each side 

 of the body which, when the skin is cast, 

 slip gently and by degrees from within the 

 body through eighteen apertures or orifices of 

 the pulmonary tubes, nine on each side. Two 

 other branches of the pulmonary pipes, that 

 are smaller and have no points of respiration, 

 cast a skin likewise. If any one separates the 

 cast little ropes or congeries of the pulmonary 

 pipes with a fine needle he will very distinctly 

 see the branches find ramifications of these 

 several pipes and also their annular compo- 

 sition." 



This really marvellous description of th<; 

 moulting of the skins of the viscera is copied 

 from Kirby and Spence, and not from Swam- 

 merdam, because I do not possess the original; 

 and much as I dislike to quote secondhand, I 



