PRAIRIE-DOGS 161 



courage to dig the owner out of their tortuous 

 depth. In the West are other similar species; 

 and all the high mountains from the Rockies 

 westward, and far to the North, have a larger 

 one which dwells near timber-line, and is known 

 as the siffleur (whistler) on account of its clear 

 sharp call. The food of all these marmots con- 

 sists of herbage and succulent roots, and they 

 do great damage in gardens where not re- 

 strained. They do not store any of this food, 

 however, but in the early autumn retire to their 

 burrows, very fat, and pass the winter in a 

 state of complete torpor, during the continu- 

 ance of which their fatness decreases, being ab- 

 sorbed to sustain the trifling exertion of life 

 caused by the continued slow beating of the 

 heart. When, therefore, they emerge early in 

 the spring, they are lean and very weak, but 

 soon recuperate on the fresh grass and herbage. 

 Their fur is of little value, and their flesh poor, 

 so that as game they are attractive only to the 

 boy and his dog, or, in the West, to hungry In- 

 dians. 



Food-value of the porcupine. Here, if any- 

 where, should be said a few words about the 



