HYBERNATION OF INSECTS. 



349 



the pupa state, the organs for taking food (except in some 

 cases in the latter) are not developed, and consequently the 

 animal is incapable of eating. The existence of insects in 

 these states during; the winter differs from their existence in 

 the same form in summer only in the greater length of its 

 term. In both seasons food is alike unnecessary, so that their 

 hybernation in these circumstances has little or nothing ana- 

 logous to that of larger animals. With this, however, strictly 

 accords their hybernation in the larva and imago states, in 

 which their abstinence from food is solely owing to the torpor 

 that pervades them, and the consequent non-expenditure of 

 the vital powers. — I shall attend to the peculiarities of their 

 hybernation in each of these states in the order just laid 

 down ; premising that we have yet much to learn on this suc- 

 ject, no observations having been instituted respecting the 

 state in which multitudes of insects pass the winter. 



It is probable that some insects of almost every order hy- 

 bernate in the egg state ; though that these must be compara- 

 tively few in number, seems proved from two considerations : 

 first, That the majority of insects assume the imago, and de- 

 posit their eggs in the summer and early part of autumn, 

 when the heat suffices to hatch them in a short period ; and 

 secondly, That the eggs of a very large proportion of insects 

 require, for their due exclusion and the nutriment of the 

 larva? springing from them, conditions only to be fulfilled in 

 summer, as all those which are laid in young fruits and seeds, 

 in the interior and galls of leaves, in insects that exist only 

 in summer, &c. The insects which pass the winter in the 

 egg state are chiefly such as have several broods in the course 

 of the year, the females of the last of which lay eggs that, re- 

 quiring more heat for their development than then exists, ne- 

 cessarily remain dormant until the return of spring. 



The situation in which the female insect places her eggs in 

 order to their remaining there through the winter, is always 

 admirably adapted to the degree of cold which they are ca^ 

 capable of sustaining ; and to the ensuring a due supply of 

 food for the nascent larvae. Thus, with the former view, 

 Acrida verrucivora and many other insects whose eggs are of 

 a tender consistence, deposit them deep in the earth out of the 



