AGE OF THE PUPA. 255 



has been, therefore, simply and entirely with a 

 view to obviate this state of things in the mind, 

 that these definitions of the different kinds of 

 pupae, which may have appeared not altogether 

 interesting, have been given. 



Having fulfilled this duty, we may now proceed 

 to the more agreeable task of ascertaining some 

 interesting facts relative to the insect's life and 

 age in the pupa state. We have already seen that 

 the insect in the larva state often arrives at a 

 very respectable old age ; indeed, in this state 

 insects live longer than either in the pupa or 

 perfect states. But pupa3 also attain to a very 

 fair number of days, sometimes living as long as 

 two years in that state. Often, however, they are 

 not more than a few days in this condition, and 

 the insect, after a short repose, springs forth a 

 new and active being. But it has been found that 

 insects live a longer or shorter period in the pupa 

 state according as the temperature of the air is 

 cold or hot. Thus, for example, when the larva 

 of a moth has become a pupa in the early part of 

 summer, the pupa state will generally not last 

 beyond a fortnight, But if, on the other hand, 

 the larva becomes a pupa late in the autumn, the 



