122 



MAMMALS OF AMERICA 



by the same cause — the presence or absence of 

 snow." 



Like a majority of predatory animals, the 

 Weasel is nocturnal in its habits. Nevertheless, 

 it is too often abroad in the daytime, either in 

 sport or on the chase, to be classed among the 

 truly nocturnal animals. In the choice and con- 



Captain Lyon states that he observed a curi- 

 ous kind of a btirrow made by Ermines in the 

 snow " which was pushed up in the same manner 

 as the tracks of moles through the earth. These 

 passages ran in a serpentine direction, and near 

 the hole or dwelling place the circles are multi^ 

 plied, as if to render the approach more intricate." 



Photograph by the U. S. Biological Survey 



BONAPARTE'S WEASEL 



The Weasel is a skilful climber, darting along the limbs of trees with the nimble- 



ness of a Squirrel 



struction of its retreats we see little evidence of 

 burrowing instincts. It retreats beneath stone 

 heaps in dense thickets, under logs and stumps, 

 in hollow trees, and also in burrows, though 

 these are usually those made by other animals 

 that it has driven off or destroyed. Neverthe- 

 less, there is evidence that it sometimes digs. 



Audubon has a passage of similar effect: " We 

 have frequently observed where it has made long 

 galleries in the deep snow for twenty or thirty 

 yards, and thus in going from one burrow to 

 another, instead of traveling over the surface, 

 it had constructed for itself a kind of a tunnel 

 beneath." 



