STATES OF INSECTS. 211 



as one of us should, when newly clothed after a long im- 

 prisonment, to the filthy prison garments we had put off. 

 It will not suffer this memento of its former state to re- 

 main near it, and is no sooner suspended in security than 

 it endeavours to make it fall. For this end — it seizes, 

 as it were with its tail, the threads to which the skin is 

 fastened, and then very rapidly whirls itself round, often 

 not fewer than twenty times. By this manoeuvre it ge- 

 nerally succeeds in breaking them, and the skin falls 

 down. Sometimes, however, the first attempt fails : in 

 that case, after a moment's rest, it makes a second, twirl- 

 ing itself in an opposite direction ; and this is rarely un- 

 successful. Yet now and then it is forced to repeat its 

 whirling, not less than four or five times : and Reaumur 

 has seen instances where the feet of the skin were so firmly 

 hooked, that after many fruitless efforts the pupa, as if 

 in despair, gave up the task and suffered it to remain a . 

 After these exertions, it hangs the remainder of its exist- 

 ence in this state until the butterfly is disclosed. 



We are now to consider the second mode of suspen- 

 sion, in which larva? by means of a silken girth round 

 their middle, fix themselves horizontally under leaves, &c. 

 These follow the same process with that of those last de- 

 scribed, in spinning a small hillock of silk to which they 

 fasten their hind legs ; and if the operation concerned the 

 larva state alone, this would be sufficient, as by means of 

 this support, and of their prolegs, they could easily re- 

 tain themselves in a horizontal position. But these lar- 



a Bonnet is of opinion that this twirling process is not with any 

 view to get rid of the exuviae, but is caused only by the irritation oc- 

 casioned by the spines of the skin of the caterpillar when they touch 

 that of the pupa. CEuv. ii. 109. 



p 2 



