CLASSIFICATION. 



Aristotle is supposed to have been the first 

 naturalist who regarded fishes as a distinct class of 

 animals, though he seems not to have understood 

 their very peculiar organization. Pliny was the 

 next writer of antiquity who devoted much atten- 

 tion to them, though from the earliest ages of the 

 world, they were an important article of food, as 

 much as at the present day. 



Without detailing the classifications of a series 

 of distinguished writers, those of Linnaeus and Cu- 

 vier are now generally adopted. Had that great and 

 good man, Cuvier, been permitted to live a 

 few more years, he would probably have completed 

 that splendid work on fishes, which occupied 

 many years of his industrious life — and which, on 

 a dying bed, he spoke of leaving in an unfinished 

 condition, with the deepest interest and regret. 



Linnaeus divided these animals into five orders : 



1. Apodal, — with bony gills, and no ventral fins. 



2. Jugular, — with bony gills, and ventral fins before the 

 pectoral. 



3. Thoracic, — with bony gills, and ventral fins under the 

 throat. 



