THE BUTTERFLY VIVARIUM. 13 



The caterpillars, thus placed as nearly as 

 possible in a state of nature, performed their trans- 

 formations perfectly and healthily ; and many of the 

 matchless specimens, which now form the chief 

 ornaments of Mr. Doubleday's celebrated collection, 

 were, I believe, reared in that manner. 



I have since had a similar contrivance in active 

 operation in my own garden, in which I have been 

 almost invariably successful in rearing to the perfect 

 state every caterpillar introduced. But the objec- 

 tion to this arrangement is, that I was seldom 

 enabled to observe the transformations at the time 

 when they were most interesting. The case being at 

 some little distance from the house, I could not 

 visit it often enough to make sure of catching my 

 proteges at the very moment of casting the skin, 

 suspending or burying themselves for change, or 

 spinning their cocoons in preparation for their 

 coming transformation to the chrysalis state. Nor 

 was I, except in a very few instances, ever in time 

 to witness the escape of the moth or butterfly from 

 the pupa case, and so be enabled to observe the 

 sudden growth of the wings from a diminutive size 

 to their full extent, which, in some insects, takes 

 place in a few minutes — the rapid increase of size 

 being distinctly visible. 



