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which resembles that of a pug-dog. They are very shy, timid animals. On first 
seeing a human being, they try to hide away, but on being aroused are savage 
enough. . . They come out of their burrows about sundown to get their food, and 
again at daylight in the morning.” Mr. Allen proceeds to say that the food of this 
sewellel is mainly composed of aquatic plants, especially the stems of a water-lily; 
and he adds that the burrows of these animals are always on the lower part of a 
hillside, and frequently have running water passing through them. Their feet are 
eminently adapted for grasping, and it is stated that these creatures are in the 
constant habit of ascending broken and small trees furnished with branches. 
They are generally captured by means of traps set in the water. 
The Beavers. 
Family CASTORIDAE. 
From the large relative size of the animals themselves, coupled with their 
extraordinary constructive and destructive powers, an amount of interest invariably 
attaches to beavers which is not vouchsafed to other members of the order to 
which they belong. As is so frequently the case in analogous instances, the 
constructive abilities and engineering capacities of these animals—marvellous 
as they undoubtedly are—have, however, been greatly exaggerated in popular 
estimation; and the creatures have been credited with performing tasks of which 
they are utterly incapable. 
Beavers, of which there are two species or varieties,—one confined to Northern 
and Eastern Europe and parts of Western and Northern Asia, and the other to 
North America,-—are the only existing representatives of the family to which they 
belong, and constitute the genus Castor. The family is characterised by the 
massive form of the skull, in which there are no postorbital processes defining the 
hinder border of the eye-sockets, and the angle of the lower jaw is rounded off*. 
There is but one pair of premolars in each jaw; and the cheek-teeth have no roots, 
a perfectly flat grinding-surface, and re-entering folds of enamel. The two series 
of cheek-teeth converge towards the front of the jaws, and the premolar in each 
jaw is larger than either of the molars. 
As a genus, beavers are characterised by their stout and heavy bodily 
conformation, this being most marked in the hinder quarters. The head is large 
and rounded, with short ears; and the tail is of moderate length, much flattened, 
and covered with a naked, scaly skin. The limbs are short, with five sharp-clawed 
toes on both the fore and hind-feet 1 ; all the toes of the hind-feet being connected 
by a web extending to the roots of the claws. The portion of the muzzle 
surrounding the nostrils is naked, as are the soles of the feet, while the ears are 
scaly. Both the ears and the nostrils are capable of being closed. The fur is 
peculiarly thick and soft, its general colour being reddish brown above, and greyer 
beneath. There is, however, some amount of individual variation in this respect, 
individuals from northern regions inclining to be darker in coloration than those 
from the southern districts of the habitat of these animals. Occasionally pied or 
1 There is an additional claw on the second toe of the hind foot, probably employed in dressing the fur. 
