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 he met with in the coldest parts of North America, 

 though it seems that its cranium and hones 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. 



CETACEA. 



The 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 vertebrae, 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 mamms 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 no 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 Wliales, we add others formerly 

 confounded with the Morses. 



