482 



Order I. — Whales. 



Cetacea* 



The Mammalia are all hot-blooded and air-breath- 

 ing animals; nevertheless, even from tliis highly- 

 organized and highly-gifted Class, numerous races have 

 been selected, whose element is the ocean, whose 

 home is in the deep. The inhabitants of the earth 

 have theh bodies supported upon four legs, so that 

 they are necessarily restricted in their growth, and 

 their bulk is apportioned to the strength of the limbs 

 that bear their weight ; but, in the water, being 

 buoyed up on every side by the denser medium, the 

 size of aquatic animals becomes of little consequence ; 

 thus the Whales attain prodigious dimensions, and, 

 from the inexhaustible supply of food >\ith which 

 they are surrounded, find abundant materials for their 

 sustenance. 



The Cetacea are mammalia altogether deprived of 

 hinder limbs. The trunk of their body is prolonged 

 without any line of demarcation into a thick tail, 

 terminated by a broad fin, very much resembling in 

 its general shape that of a fish, but entirely composed 

 of an expansion of the skin supported by a tough 

 cartilaginous substance, and, instead of being placed 

 vertically, to strike the water from side to side, it is 

 horizontal, so that by means of its upward and down- 

 ward movements, these animals easily come to the 

 surface, or plunge perpendicularly into the depths 

 below ; their head is joined to the body without the 

 intervention of any apparent neck, and their arms, 

 the representatives of the fore-limbs of quadrupeds, 

 are so flattened and concealed by the skin, that they 

 might easily be mistaken for pectoral fins. When 

 denuded of their flesh, however, they present, under a 

 modified shape, bones and fingers corresponding with 

 those met with in the Lion or the Bat. Thus, con- 



* KTJTos, cetos, a whale. 



