deposited the winter food-supply. The constant 

 flow of the spring water prevented thick ice from 

 forming, both around the food-pile and between 

 it and the house-entrance. 



Large numbers of beaver do not possess a 

 house. Beaver who live without a dam or pond 

 commonly do not build a house, but are content 

 with a burrow or a number of burrows in the 

 banks of the waters which they inhabit. In the 

 severe struggle to live, there is a tendency on 

 the part of the beaver to avoid the building of 

 dams and houses, as these reveal their presence 

 and put the aggressive trapper on their trail. 



Many colonies have both houses and burrows. 

 Apparently the houses were used in the winter- 

 time, the burrows in summer. One beaver bur- 

 row which I examined was about one foot above 

 the level of the pond and twelve feet distant 

 from it. The entrance tunnels were sixteen feet 

 in length, and began a trifle more than three 

 feet under water near the edge of the pond. This 

 burrow measured five and a half feet long, about 

 half as wide, and seventeen inches high. It was 

 immediately beneath the outspreading roots of 

 127 



