HYBERNATION OF INSECTS. 553 



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 Melolontha, Elateres, Cerambyccs, Buprcstes, and several species 

 of Libelhila, Ephemera, &c. There are also many larvaj 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 Woebcrana 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 pro- 

 vident of comfort, prepare themselves an artificial habitation. With this 

 view the larva of Cossus Ugniperda, as formerly observed in describing 

 the habitations of insects, forms a covering of pieces of wood lined with 

 fine silk ; those o^ Hep iol us Hamuli, Xylina radicea, and some other moths, 

 excavate under a stone a cavity exactly the size of their bodies, to which 

 they give all round a coating of silk^, and the larvae of Pieris Cratcegi 

 inclose themselves in autumn in cases of the same material", and thus pass 

 the cold season, in small societies of from two to twelve, under a common 

 covering formed of leaves. Bonnet mentions a trait of the cleanliness of 

 these insects which is almost ludicrous. He observed in one of these nests 

 a sort of sack containing nothing but grains of excrement ; and a friend 

 assured him that he had seen one of these caterpillars partly protrude itself 

 out of its case, the hind feet first, to eject a similar grain ; so that it would 

 seem the society have on their establishment a scavenger, whose business 

 it is to sweep the streets and convey the rejectamenta to one grand reposi- 

 tory!^ This, however singular, is rendered not improbable from the fact 

 that beavers dig in their habitations holes solely destined for a like pur- 

 pose"*, as also do badgers. 



A very considerable number of insects hybernate in the perfect state, 

 chiefly of the orders Coleoptera, Hemiptera, Hymenoptera, and Diptera, 

 and especially of the first. Vanessa Urticce, lo, and a few other lepidop- 

 terous species, with a small proportion of the other orders, occasionally sur- 

 vive the winter ; but the bulk of these are rarely found to hybernate as 

 perfect insects. Of coleopterous insects, Schmid, to whom we are 

 indebted for some valuable remarks on the present subject^, says that he 

 never found or heard of any entomologist finding a hybernating individual 

 of the common cock-chafer (JMeloloniha vulgaris), or of the stag-beetle 

 {Lucanus Cervus) ; and suggests that it is only those insects which exist 

 but a short period as larvae, as most of the tribe of weevils, lady-birds, 



' Brahm, Ins. Kal. ii. 59. 118. 



* I have reason to think that the larvae of some species of Hemerobius thus protect them- 

 selves by a net-like case of silken threads ; at least I found one to-day (December 3d, 1816) 

 inclosed in a case of this description concealed under the bark of a tree ; and it is not very 

 likely that it could be a cocoon, both because the inhabitant was not a pupa, which state, 

 accordmg to Reaumur, is assumed soon after the cocoon is fabricated (iii. 3S5.), and because 

 the same author describes the cocoons of these insects as perfectly spherical and of a very 

 close texture (384.), while this was oblong, and the net-woik with rather wide meshes. 



» CEmi;. li. 72. •« Ibid. ix. 167. * Illig. Mag. i. 209—228. 



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