175* 



and this structure is that which is peculiar to the insect 

 in' the state of a caterpillar. The fifth body, which is 

 very different, is that of the chrysalis. The respective 

 stak- of tlu'se bodies are in proportion to their distance 

 from the centre of the animal. Those that are the far- 

 thest oil have more consistence, or unfold themselves 

 soonest. 



WiK-ji the -exterior body has attained its full growth, 

 the interior, which immediately follows, is considerably 

 unfolded. It soon finds itself lodged in too narrow a 

 compass : it stretches on all sides the sheaths that en- 

 compass it. The vessels which convey the nourishment to 

 these coverings being broken or stifled by this violent 

 distension, cease to act. Tic skin wrinkles and n:!es 

 up : at length it opens, and the insect appears clothed 

 with a new skin and new organs. 



A fast of "a day or two precedes each moulting. It 

 is probably occasioned by tiie violent state in winch all 

 the organs then are. Perhaps it might be also neces- 

 sary, in order to promote the success of the operation, 

 and prevent obstructions: be this as it may, the insect is 

 Weak after every moulding: all its organs a^e yet af- 

 fected by 'the state they were in under the covering they 

 are just disengaged from. The scaly parts, as the head 

 and legs are almost entirely membraneous, and are all 

 imbued with a liquor that insinuates itself betwixt the 

 two skin*, and facilitates their separation. But this 

 moisture evaporates by degrees : all the parts acquire a 

 consistence, and the insect is in a condition to act. The 

 first use that some species of caterpillars, which live 

 only on leaves, make of their new teeth, is to devour 

 greedily their spoils ; sometimes they will not even 

 wait for doing it till their jaws have received their full 1 

 degree of .strength. Can these spoils be a proper ali- 

 ment to renew and increase their strength? Some 

 caterpillars have likewise been seen to gnaw the shells 

 of their eggs after they have issued from then), and' 

 even that of the eggs of such caterpillars as. have not 

 been hatched. 



