( Originally Published 1936 )
The Beavers are aquatic animals, easily distinguished from allied forms by their naked, scaly, and usually flattened tails and webbed hind-feet.
Beaver (Castor fiber)
The Beaver is one of the largest rodents, growing to the length of nearly four feet. Its body is stout, and broadest behind, the legs are short and strong, and the hind feet are completely webbed. The tail is very broad and flat, and for the greater part of its length is scaly and furrowed; the fur, which is very soft and silky, is chestnut-brown above and lighter below. See Plate i6, Fig. 74. Until within the last few centuries, the Beaver was common on the banks of streams and rivers over almost the whole of Europe and Northern Asia, but it has long been extinct in Great Britain, and is now either extinct or very scarce and local in most of the countries where it formerly existed in great numbers. It lives in bur-rows on the banks of rivers.
The closely-allied American Beaver (Castor canadensis) cuts down trees with its strong teeth, making dams in streams with branches, stones, mud, and so forth, and within the ponds so formed, these animals build dome-shaped houses in which they live, and in which they hibernate during the winter. Their food consists chiefly of the bark of trees and the roots of water plants. The Beaver was formerly much hunted, both for the fur, which was used to make beaver hats and other articles of clothing, and to obtain castoreum, an odoriferous substance used in medicine, which is secreted by two glands near the extremity of the body. The flesh of the Beaver is said to taste like pork.
Musquash, or Muskrat (Fiber zibethicus)
The Musquash, or Muskrat, is a native of North America, where it lives in burrows on the banks of rivers, or forms lodges, similar to those of the beaver, but smaller. The tail is long, narrow, and scaly, but, unlike that of the beaver, is flattened vertically, and acts as a rudder. The animal is large, reaching a length of nearly two feet, including the tail; the fur is reddish-brown above, paler below, and has considerable value. See Plate 17, Fig. 34. The Muskrat is hunted also for the sake of its flesh, which is eaten, notwithstanding its strong musky odour.