HYBERNATION OF INSECTS. 431 



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 Melolon- 

 thce, Elateres, Cerambyces, Buprestes, and several species 

 of Libellula, Ephemera, &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 Wcelerana and others 

 of the same family ; of the second broods of several but- 

 terflies, &c. Many of these residing in the ground or 

 in the interior of trees need no other hybernacula 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 artificial habitation. With this view the 

 larva of Cossus ligniperda, as formerly observed in de- 

 scribing the habitations of insects a , forms a covering of 

 pieces of wood lined with fine silk ; those of Hepiolus 

 Humuli, Xylina radicea, and some other moths, exca- 

 vate under a -stone a cavity exactly the size of their 

 bodies, to which they give all round a coating of silk b , 

 a VOL. I. 452. b Brahm, Ins. Kal. ii. 59. 118. 



