THE BEAVER 



(Castor fiber) 



THE beaver enjoys the distinction of being the only warm-blooded quadruped 

 that is in the habit of making really noticeable modifications in the 

 appearance of the earth's surface. Many quadrupeds, such as foxes, 

 ant-bears, rabbits, and rats and mice burrow holes in the ground, while the mole 

 marks the course of its subterranean tunnels by throwing up heaps of earth at 

 intervals. But although such excavations and hillocks, when sufficiently numerous, 

 may to a slight degree affect the appearance of a meadow, they are nothing 

 in comparison to the changes brought in a valley by a colony of beavers. By 

 throwing a dam across its course, these industrious rodents will convert a narrow 

 stream into a wide sheet of stagnant water, which in the course of time may 

 become silted up so as to form a broad and level "beaver-meadow," where there 

 was originally a rocky valley. In or near their dams beavers likewise construct 

 dwellings of mud and clay, known in America as "lodges," for their own 

 accommodation. 



But this is by no means all beavers accomplish in the way of "public 

 works," for, by means of the single pair of powerful chisel-like teeth in the fore 

 part of each jaw and the powerful muscles by which the jaws themselves are 

 worked, these animals, which are about the size of an ordinary spaniel, are enabled 

 to fell trees of considerable size, which are used in the construction of their dams. 



Beavers are the sole living representatives of a family of rodents allied on 

 the one hand to squirrels and dormice, and on the other to rats and mice. Two 

 structural peculiarities are very characteristic of these rodents. In the first place, 

 one of the toes of the fore-foot is provided with a double claw, which may be used 

 in dressing the beautiful, long brown fur ; a similar structure occurring in the smaller 

 rodent known as the Arctic lemming {Dicvostonyx torquatus). Secondly, there is 

 the remarkable flattened, scaly tail, which almost looks as though it did not belong 

 to the animal, although in reality, except for its superior size, it is not much more 

 abnormal than the scaly cylindrical tail of the rat. Several myths attach to the 

 beaver's tail ; it was said, for instance, to be employed as a trowel for plastering 

 down the mud used in building the dams and lodges, although its real use is to act 

 as a rudder in swimming, more especially when its owner is transporting the trunk 

 of a felled tree. When entering the water, or when engaged in playing therein, the 

 beaver frequently makes a resounding "smack" by striking the surface with its tail. 



In monkish times beaver-tail was considered to partake more of the nature 

 of fish than flesh, and was consequently allowed to be eaten on fast days. This was, 



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