as though a remarkable discovery had been 

 made; and immediately he started to dig rapidly 

 with his fore paws, as if some good thing were 

 buried just beneath. He may have been only 

 pretending, however. Without uncovering a 

 thing, he presently raced forward to overtake 

 Mother Grizzly. 



The hibernating habits of the grizzly are not 

 completely understood. The custom probably 

 originated, as did the hibernation of other ani- 

 mals, from the scarcity of food. In a long ac- 

 quaintance with the grizzly my study of his 

 hibernation has brought scanty returns, though 

 all that I have actually seen has been of the 

 greatest interest. 



The grizzly hibernates each winter, — "dens 

 up" from three to four months. The length of 

 time is determined apparently by latitude and 

 altitude, by the snow-fall, weather conditions, — 

 whether severe or mild, — and the length of 

 the winter; and perhaps, also, by the peculiari- 

 ties or the condition of the individual animal. 

 Commonly he hibernates in high altitudes, many 

 going to sleep near or above the timber-line. 



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