HYBERNATION. Ill 



rupeds t we may observe that different species 

 are led by unerring instinct to choose different 

 kinds of winter dormitories, and make different 

 arrangements. The marmot excavates a deep 

 burrow, in which it makes a bed of dried grass 

 and moss, to which it retires in autumn. Among 

 burrowing quadrupeds, the hamster is remark- 

 able for the extent of its underground galleries 

 and chambers, which constitute its summer 

 abode and winter asylum. The dormouse 

 makes a nest in the crevice of a tree, or in the 

 thickest part of a dense brake, to which it 

 retreats, coiling itself up into a ball, and thus in 

 its snug dome-covered dormitory, made of moss 

 and herbage, awaits the approach of sleep. The 

 hedgehog makes a warm soft nest of moss and 

 leaves, under the root of some old tree, in the 

 hole of a bank, under the covert of logs or 

 masses of timber, and there passes the winter 

 in profound repose. The mole descends deeper 

 into the soil in winter, but does not hybernate ; 

 on the return of spring it leaves its deep 

 fortress, and commences its labours on the 

 surface of the earth. Whether the shrewmouse 

 hybernates, in the strictest sense of the word, 

 we do not well know ; most probably it does so 

 to a certain extent during the inclemency of 

 mid-winter. Bats hybernate in the hollows of 

 trees, in old ruins, in church-towers, in barns, 

 in caves, and similar localities ; they make no 

 nest, but hang suspended by the hinder claws. 

 In every case, however, the aim seems to be to 

 secure a shelter from extreme cold, and the 



