222 GNAWING ANIMALS 



serviceable when the animal is propelling a log to a desired 

 spot. 



In winter, the wolverene, the inveterate foe of the 

 Beaver family, comes across the ice to a lodge. But the 

 compost of mud and moss is frozen into almost the solidity 

 of concrete, that would offer good resistance to iron tools, 

 and the carnivore's claws make little impression upon it. 



Though the Beaver does not hibernate, it is far less 

 active in winter, only leaving the lodge to pay a visit to the 

 heap of logs fastened down in the mud. Having dragged 

 a log out of the store, the Beaver eats the bark and then 

 usually applies the timber to strengthen the dam. In 

 summer the animal eats the roots and stems of various 

 aquatic plants, but bark is its staple diet. 



The Beaver is hunted for its fur, which is employed for 

 expensive articles of apparel. It also yields castoreum, 

 which is obtained from two glands near the end of the 

 body. At one time used in medicine, the odoriferous sub- 

 stance is now chiefly employed in perfumery. Beavers can 

 scent castoreum at a considerable distance, and are irresis- 

 tibly attracted by it. When a hunter sets a trap he fixes 

 it about six inches below the surface of the water, and from 

 it projects a twig that has been dipped in castoreum, or 

 ' barkstone,' as the trappers call it. The Beaver, drawn to 

 the spot by the powerful odour, often falls a victim to the 

 hidden snare. 



It is asserted that sometimes are found lazy Beavers who 

 will not assist in building dams or lodges. As these drones 

 are usually males, it is most probable that they have 

 been conquered by their stronger brethren in fights for 

 partners, and then driven out of the community, to 

 become idlers from necessity rather than from choice. 



MOUSE-LIKE RODENTS. 

 FAMILY MURID^E. 



The Muridae is the largest and most typical family of the 

 Rodents. They are mainly small animals, and include some 

 of the tiniest of the mammals. Mice and Rats are almost 



