66 HISTORY OF 



skin of the aurelia, before it eats its way through 

 the external covering which its own industry has 

 formed round it. In order to observe the man- 

 ner in which it thus gets rid of the aurelia cover- 

 ing, we must cut open the cone, and then we 

 shall have an opportunity of discovering the in- 

 sect's efforts to emancipate itself from its natural 

 shell. When this operation begins, there seems 

 to be a violent agitation in the humours contained 

 within the little animal's body. Its fluid seems 

 driven, by a hasty fermentation, through all the 

 vessels, while it labours violently with its legs, 

 and makes several other violent struggles to get 

 free. As all these motions concur with the 

 growth of the insect's wings and body, it is im- 

 possible that the brittle skin which covers it 

 should longer resist ; it at length gives way, by 

 bursting into four distinct and regular pieces. 

 The skin of the head and legs first separates j 

 then the skin at the back flies open, and dividing 

 into two regular portions, disengages the back 

 and wingg ; then there likewise happens another 

 rupture in that portion which covered the rings 

 of the back of the aurelia. After this, the but- 

 terfly, as if fatigued with its struggles, remains 

 very quiet for some time, with its wings pointed 

 downwards, and its legs fixed in the skin which 

 it had just thrown off. At first sight, the animal, 

 just set free, and permitted the future use of its 

 wings, seems to want them entirely ; they take up 

 such little room, that one would wonder where 

 they were hidden. But soon after, they expand 

 so rapidly, that the eye can scarcely attend their 



