54 FISHES. Class IV. 



Explan. PI. j%". 2. the Picked Shark. 

 a. The lateral apertures. 



VI. LAMPREY. 



VII. HAG. 



VIII. RAY. 



IX. SHARK. 



X. ANGLER. 



XL STURGEON. 



XII. TETRODON. 



XIII. SUCKER. 



XIV. PIPE FISH. 



XV. TRUMPET FISH. 



Div. III. BONY FISHES. 



A HIS division includes those whose muscles 

 are supported by bones or spines, which breathe 

 through gills covered or guarded by thin bony 

 plates, open on the side, and dilatable by means 

 of a certain row of bones on their lower part, 

 each separated by a thin web ; which bones are 

 called the Radii Branchiostegi, or the Gillcover- 

 ing Rays. 



The tails of all the fishes which form this divi- 

 sion, are placed in a situation perpendicular to 

 the body, and this is an invariable character. 



Some Icthyologists have lately attempted to 

 make the number of the branchiostegous rays a 

 character of the genera ; but I found (yet too 

 late in some instances, where I yielded an im- 



