142 
The Mammals of Colorado 
Arapahoe, Gunnison, Delta, Garfield, Eagle, El Paso, Teller, and 
Mineral counties. No doubt it is found in others. 
FIG. 47. BEAVER, Castor c. frondator. 
Side view of skull x 
Habits. — The habits of the Beaver are so well known in 
a general way that it hardly seems worth while to say much 
about them. The animal lives a semi-aquatic life, always 
living where there is water, and having its home either in 
holes in the bank of the stream or pond, or else living in a 
house or lodge built of sticks and mud. If the water in the 
stream or pond is not sufficient for its needs a dam may 
be built to increase the depth of water. These dams are 
constructed of sticks and mud laid packed together. Some- 
times sticks of considerable size may be used, if they happen 
to be at hand, and again at other times mere twigs are used. 
Most of the dams which have happened to come to my 
