WHALES— DOLPHINS. 373 



ORDER CETACEA. 



Whales — Dolphins. 



There is not, in the whole range of natural science, a 

 study more variously and deeply interesting than the 

 investigation of the laws by which those variations of 

 structure are governed which have for their object the 

 adaptation of the same organs to different functions in 

 animals of various forms and habits. 



The outward appearance of the Cetaceans, organized as 

 they are for a permanent residence in the ocean, resembles 

 so nearly that of the Fishes that they have been arranged 

 together by the ancients and by the ignorant. Ray him- 

 self was not prepared to separate them, and even the 

 example of the great Linnaeus, who with his wonted 

 correctness and judgment placed the Whales in their true 

 position, was not suiRcient to counterbalance the pre- 

 judices of Pennant, who regarded the Cetacea as forming 

 a division of the class of Fishes, although he was well 

 aware that they bring forth their young alive, and nourish 

 them by means of mammary organs, similarly constructed 

 to those of the whole class of Mammalia. Their true posi- 

 tion, however, being established, it becomes a matter of 

 great interest to ascertain what relation the other organs of 

 the body bear to the corresponding ones in the other groups 

 of this class, and by what modifications of structure they 

 are rendered subservient to a mode of life so diiferent 

 from that of the more typical forms. A brief notice of 

 the principal points of their organization, so far as they 



