CLASS PISCES. 415 



SALMONID^, 



Formed in Linnaeus but a single great genus, 

 precisely characterized by a scaly body, and a first 

 dorsal with soft rays, followed by a second, which is 

 small and adipose, that is, formed simply by a skin 

 filled with fat, and not supported by rays. 



These fishes have numerous cceca, and are pro- 

 vided with a natatory bladder. Almost all of them 

 ascend rivers, and their flesh is excellent. The 

 structure and armature of their jaws vary most 

 surprisingly. 



This great genus, 



Salmo, L., 

 Should be subdivided as follows : 



Salmo, Cuv. (The Salmons proper, or rather Trouts), 



Have a considerable portion of the edge of the upper 

 jaw formed by the maxillaries, a range of pointed 

 teeth in the maxillaries, the intermaxillaries, the 

 palatines, and the mandibularies, and two ranges on 

 the vomer, on the tongue, and the pharyngeals, so 

 that they are the most completely dentated of all 

 fishes. In the old males, the end of the lower jaw is 

 curved towards the palate, where there is a fossette 

 to lodge it when the mouth is closed. Their form is 

 universally known. Their ventrals correspond to the 

 middle of their first dorsal, and the second or adipose 

 dorsal corresponds to the anal. Their branchial rays 



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