356 



HYBEKNATION OF INSECTS. 



question had taken possession. 1 Most insects place them- 

 selves in their hybernacula in the attitude which they ordi- 

 narily assume when at rest ; but others choose a position 

 peculiar to their winter abode. So most of the ground- 

 beetles (Eutrechma) adhere by their claws to the under side 

 of the stone which serves for their retreat, their backs being 

 next to the ground ; in which posture, probably, they are 

 most effectually protected from wet. Gyrohypnus sanguino- 

 lentus, and other rove-beetles of the same genus, coils itself 

 up like a snake, with the head in the centre. 



The majority of insects pass the winter in perfect solitude. 

 Occasionally, however, several individuals of one species, not 

 merely of such insects as Anchomenus prasinus, a beetle, 

 Pyrrhocoris apterus, a bug, &c, which usually in summer also 

 live in a sort of society, but of others which are never seen 

 thus to associate, as Haltica oleracea, Carabus intricatus, and 

 several Coccinellce, &c, are found crowded together. This is 

 perhaps often more through accident than design, as indivi- 

 duals of the same species are frequently met with singly ; yet 

 that it is not wholly accidental seems proved by the fact that 

 such assemblages are generally of the same genus and even 

 species. Sometimes, however, insects of dissimilar genera and 

 even orders are met with together. Schmid once in February 

 found the rare Lomechusa strumosa torpid in an ant-hill, in 

 the midst of a conglomerated lump of ants, with which it was 

 closely intertwined. 2 



By far the greater proportion of insects pass the winter 

 only in one or other of the several states of egg, pupa, larva, 

 or imago, but are never found to hybernate in more than one. 

 Some species, however, depart from this rule. Thus Aphis 

 Rosce, Cardui, and probably many others of the genus, hyber- 

 nate both in the egg and perfect state 3 ; Cynthia Cardui, 

 Gonepteryx Rhamni, and some other species, usually in the 

 pupa, but often in the perfect state also ; and Vanessa Io, ac- 

 cording to the accurate Brahm, in the three states of egg, 

 pupa, and imago. 4 It is probable that in these instances the 



i Illig. Mag. i. 216. 2 Ibid. i. 491. 



3 Kyber in Germar, Magazin der Entomologie, ii. 2. 



4 Ins. Kal. ii. 188. 



