352 



HYBERNATION OF INSECTS. 



design. A few are suspended without any covering, though 

 usually in a sheltered situation. But by far the larger 

 number are concealed under leaves, in the crevices or in the 

 trunk of trees, &c, or inclosed in cocoons of silk or other ma- 

 terials, and often buried deep under ground out of the reach 

 of frost. One reason why so many lepidopterous insects pass 

 the winter as pupae has been plausibly assigned by Rosel, in 

 remarking that this is the case with all the numerous species 

 which feed on annual plants. As these have no local habita- 

 tion, dying one year and springing up from seed in another 

 quarter the next, it is obvious that eggs deposited upon them 

 in autumn would have no chance of escaping destruction ; 

 and that even if the larvae were to be hatched before winter, 

 and to hybernate in that state, they would have no certainty 

 of being in the neighbourhood of their appropriate food the 

 next spring. By wintering in the pupa state, these accidents 

 are effectually provided against. The perfect insect is not 

 ready to break forth until the food of the young, which are to 

 proceed from its eggs, is sprung up. 



To the insects which hybernate in the larva state, of 

 course belong, in the first place, all those which exist under 

 that form more than one year ; as many Melolonthce, Elateres, 

 Cerambyces, Buprestes, and several species of Libellula, Ephe- 

 mera, &c. There are also many larvae which, though their 

 term of life is not a year, being hatched from the egg in 

 autumn, necessarily pass the winter in that state, as those of 

 several Anobia and other wood-boring insects; of Semasia 

 Wceberana and others of the same family; of the second 

 broods of several butterflies, &c. Many of these residing in 

 the ground, or in the interior of trees, need no other hyber- 

 nacula than the holes which they constantly inhabit ; some, 

 as the aquatic larvae, merely hide themselves in the sides or 

 muddy bottom of their native pools ; while others seek for a 

 retreat under moss, dead leaves, stones, and the bark of 

 decaying trees. Most of these can boast of no better winter 

 quarters than a simple unfurnished hole or cavity ; but a 

 few, more provident of comfort, prepare themselves an arti- 

 ficial habitation. With this view the larva of Cossus lig- 

 niperda, as formerly observed in describing the habitations 



