BUTTERFLIES IN WINTER. 257 



eight months, to a fortnight, or to five, or to six 

 weeks in different instances. Five or six days 

 seemed to be equal to a month of the natural 

 temperature. The butterflies thus developed were 

 in no respect different from those which are 

 brought into activity at the natural period. 

 They were as active and perfect, as if their time 

 and place of birth had been the green fields, 

 instead of amidst the strange vegetation of these 

 splendid Conservatories. Several of the mother 

 insects deposited their eggs, accomplishing the last 

 act of their existence as if summer had come, and 

 died while the frosts and snow held all external 

 nature yet in bondage. Not only, therefore, was 

 the duration of the pupa state in these insects 

 shortened, but their whole life was thus abridged 

 by several months. 



In November of the same year Reaumur re- 

 commenced his experiments, and again exposed a 

 number of pupae to the genial influence of these 

 hot-houses. The result was the same. In the 

 first week in December butterflies appeared, which 

 would not, in natural circumstances, have been 

 developed earlier than the May of the next year. 

 There were some pupse, in particular, whose de- 

 s 



