THE MOTH. 311 



Mode of feeding and changing into a chrysalis. 



Its covering being thus formed, it never quits it 

 but in cases of the most urgent necessity. When 

 it wants to feed, it puts out its head at either end 

 of its case, as best suits its conveniency. When 

 it wishes to change its place it puts out its head, 

 and its six fore legs, by means of which it moves 

 forward, taking care first to fix its hind legs into 

 the inside of the case so as to drag it along. In 

 this manner it lives till, by the augmentation of its 

 size its case becomes too small for the body : when 

 this is felt it begins by making a small addition 

 to one end ; then, turning itself within the case, 

 which is always wide enough in the middle for 

 that purpose, it makes a little addition to the 

 other end, so as still to preserve the widest part 

 exactly in the middle; and in the same manner 

 it makes every successive addition. For this 

 purpose the insect has teeth like scissars, and 

 when widening its case, it begins by making a 

 slit lengthways, from the centre to one of the 

 extremities. This opening it instantly fills up 

 with a thin stripe of wool externally, and silk in- 

 ternally, in the same manner as in the other 

 parts. It afterwards, at a little distance from 

 this, makes another slit at the same end, which 

 it also fills up; then, turning itself within, it re- 

 peats the same process, from the centre to the 

 other end. 



In this case the animal changes into a chrysa- 

 lis, and, in about three weeks, issues a small- 

 ivinged nocturnal moth, of a silvery-grey colour. 



