HYBERNATION OF INSECTS. 431 



culty, common also to some of the larger animals, of 

 passing- the winter in a state of torpor — by ordaining 

 that the insect shall live through that period, either in 

 an incomplete state of its existence wlien i*s organs of 

 nutrition are undeveloped, or, if the active part of its 

 life has commenced, that it shall seek out appropriate 

 hyhernacula or vrinter quarters, and in them fall into 

 a profound sleep, during which a supply of food is 

 equally unnecessary. 



In two of the four states of existence common to in- 

 sects, in which different tribes pass the winter, namely, 

 the egg and 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 win- 

 ter, differs from their existence in the same form in sum- 

 mer only in the greater length of its term. Iti both 

 seasons food is equally unnecessary, so that their h}-- 

 bernation in these circumstances has little or nothing 

 analogous to that of larger animals. With this, how- 

 ever, 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 sub- 

 ject, no observations having been instituted respect- 

 ing the state in which multitudes of insects pass the 

 winter. 



It is probable that some insects of almost every order 

 bybernate in the e^g state : though that these must bo 



