CETACEA. 181 
the forehead is convex, and the end of the muzzle furnished with 
hairs. It stands low, and is covered with tufted hair that reaches to 
the ground. The tail is extremely short. It diffuses more strongly 
than any other species the musky odour common to all the genus. 
It is only to be met with in the coldest parts of North America, 
though it seems that its cranium and bones have been carried by the 
ice to Siberia. The Esquimaux make caps of the tail, the hairs of 
which, falling over their face, defend them from the Musquitoes. 
ORDER IX. 
aS 
CETACEA. 
Tue Whales are mammiferous animals without hind feet; their trunk is 
continuous, with a thick tail, terminating in an horizontal, cartilaginous 
fin, and their head is united to the trunk by a neck, so thick and short, 
that no contraction of it can be perceived; it is composed of a very slen- 
der cervical vertebre, which are partly cemented to one another. The 
first bones of the anterior extremities are shortened, and the succeeding 
ones flattened and enveloped in a tendinous membrane, which reduces 
them to true fins. Their external form is altogether that of fishes, the 
tail fin excepted, which in the latter is vertical. They always therefore 
remain in the water; but as they respire by lungs, they are compelled to 
return frequently to its surface to take in fresh supplies of air. Inde- 
pendently of this, their warm blood, their ears, with external, though 
small, openings, their viviparous generation, the mamme through the 
medium of which they suckle their young, and all the details of their 
anatomy sufficiently distinguish them from fishes. 
Their brain is large, and its hemispheres well developed; the petrous 
bone, or that portion of the cranium which contains the internal ear, is 
separated from the rest of the head, and only adheres to it by means of 
ligaments. There are uo external ears, nor hairs upon the body. 
The form of their tail compels them to flex it from above downwards 
to produce a progressive motion; it also greatly aids them in rising in the 
water. 
To the genera hitherto described of the Whales, we add others formerly 
confounded with the Morses. 
