210 STATES OF INSECTS. (Larva.) 
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 ma- 
- noeuvre it generally 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, twirling itself in an opposite direction ; and this 
is rarely unsuccessful. 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*. After these exertions, it hangs the re- 
mainder of its existence in this state until the butterfly | 
is disclosed. 
We are now to consider the second mode of suspen- 
sion, in which larvae 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- 
* Bonnet is of opinion that this twirling process is not with any 
view to get rid of the exuviz, but is caused only by the irritation oc- 
casioned by the spines of the skin of the caterpillar when they tcuch 
that ofthe pupa. Guz, 11, 109. 
