THE NEW-YORK FAUNA. 



CLASS V. FISHES. 



VERTEBRATED ANIMALS WITH COLD RED BLOOD ; BREATHING BY GILLS THROUGH THE MEDIUM 

 OF WATER ; WITHOUT LUNGS. BODY COVERED MOSTLY WITH IMBRICATED SCALES OR 

 PLATES, OR WITH A SMOOTH MUCOUS SKIN. MOVE IN WATER BY MEANS OF FINS INSTEAD 

 OF FEET, WHICH VARY IN NUMBER. REPRODUCTION BY EGGS, WHICH ARE USUALLY FECUN- 

 DATED AFTER EXCLUSION. HEART UNILOCULAR, OR COMPOSED OF ONE AURICLE AND ONE 

 VENTRICLE. HEAD VARIOUS ; NO NECK. AQUATIC. CHIEFLY CARNIVOROUS. 



Obs. The animals of this class are very numerous, and are readily distinguished from all 

 Others. About four thousand were assembled together by Cuvier when he first began to study 

 them, but the actual number now known is supposed to reach double that amount. 



Fishes have been divided into two great groups, viz. the Bony, and the Cartilaginous. 

 The first comprises by far the greatest number of species. 



SUB-CLASS I. BONY FISH. 



Skeleton bony, the osseous matter being deposited in fibres. Sutures of the cranium distinct. 

 With inaxillary or intermaxillary bones, always one and generally both, present. Gill 

 membrane with rays. 



Section 1. Pectinibranchh. 



Gills arranged in continuous rows like the teeth of a comb. Furnished toith an opercle or 

 gill cover, which is bordered with a loose membrane supported by rays. Jaws complete 

 and free. 



Obs. This section embraces two orders, characterized chiefly by the presence or absence 

 of spinous rays. 



Fauna — Part 4. 1 



