122 WONDERS OF ORGANIC LIFE. 



lair in the frozen snow ; the falling snow drifts 

 over the den, covering it to a great depth, a 

 small aperture for breathing being always 

 open. In this retreat, about the latter part of 

 December, she brings forth two cubs, and in 

 March quits the den with them, then about as 

 large as a shepherd's dog, and prowls abroad, 

 lean, gaunt, and ferocious ; hunger, and the 

 presence of her offspring, adding fury to her 

 savage temper. The male wanders about the 

 marshes and adjacent parts until November ; 

 he then goes out to sea in quest of seals, and 

 becomes very fat. It often happens that he 

 becomes drifted out from the coast on a floating 

 field of ice." 



In these accounts of three species of bears 

 we are presented with different modifications of 

 hybernation. First, the common brown bear 

 hybernates, but whether in a state of torpidity 

 or not is very doubtful ; the female cannot 

 become torpid, and the reason is obvious. 

 Secondly, the American black bear does not 

 invariably hybernate ; their males wander 

 southward, but the females seek a winter re- 

 treat, not for the sake of slumber, but as a 

 nursing den. Thirdly, the male of the Polar bear 

 roams about in quest of prey during winter ; 

 while the female, in her snow-covered seclusion, 

 brings forth and nourishes her young. 



Thus, then, there are grades in the state of 

 hybernation, from continuous torpidity to partial 

 torpidity, and thence to wakeful activity. Then 

 we come to accidental seclusion, with or without 



