Feb., 1912. Mammals of Illinois and Wisconsin — Cory. 371 



to my knowledge, show any preference for the vicinity of water either 

 to its hunting grounds or its retreat. It appears generally to prefer 

 hilly and rocky regions. It is said not to burrow readily, but tisually 

 to take possession of the burrow of another animal, or to choose its 

 retreat in some natural crevice among rocks, or in slight excavations 

 formed by itself under trees. I have generally found it occupying the 

 burrow of the common ground-squirrel {T ami as striatus), and have 

 sometimes known it to live in hollow logs in summer. It often travels 

 under snow, through pathways constructed like those of the shrews 

 and meadow -mice ; and I have traced these snow-covered ways for many 

 rods, where the weasel had evidently been in search of prey. Some of 

 these had been travelled repeatedly and for a long time, though few 

 tracks were seen on the surface. In consequence of this habit, the 

 presence of the animal is sometimes not noticed. 



"In its winter quarters, the weasel forms a large, wami nest, like 

 that of the mink. Five young are commonly produced in the early 

 part of summer; and these, I am infonned, remain with the mother, or 

 at least keep together in the same neighborhood till autumn, when they 

 separate, and, like the mink, lead a solitary life, the males only joining 

 the females in the pairing season. This is in the latter part of February, 

 at which time the males are very active, wandering far from their 

 burrows in search of the females. I cannot say whether this species 

 ever inhabits the prairie at a distance from the woods. It may be that 

 all the weasels found living on the prairies of Illinois are of the smaller 

 species, Putorius cicognanii. All the weasels identified with the PiUorius 

 noveboraccnsis, which I have observed, were taken in the woods. This 

 species is not a tree-climber any more than the mink; but it has occa- 

 sionally been seen to ascend trees, and I am infomied of a remarkable 

 instance in which one was observed to pursue and overtake a ground- 

 squirrel upon a tree." (/. c, 185S, pp. 105-106.) 



As illustrating the ferocity of these animals. Dr. C. Hart Merriam 

 says : * 



"I once put a very large rat into a square tin cage with a Weasel 

 of this species. The rat had been caught in a steel trap by the toes of 

 one of its hind feet, and was in no way injured. He was very ugly, 

 biting fiercely at the trap and the stick with which I assisted him into 

 the cage with the Weasel. No sooner had he entered the cage than his 

 whole manner and bearing changed. He immediately assumed an 

 attitude of abject terror, trembling from head to foot, and crawled into 

 the nearest corner. The Weasel advanced toward him at once, and as 

 he did so the rat raised on his hind legs, letting his fore paws hang 



* Mamm. Arlironclack Reg., 1886, p. 57. 



