FISHES. 



579 



bones of the shoulder. It is much the more numerous and im- 

 portant of the order. It includes most of our fresh-water fishes, a 

 great number of marine species, and many like the salmon, which be- 

 take themselves to the rivers in the spawning season to deposit their 

 ova. We shall limit our remarks to the Salmonida, the Clupeadce, 

 and 'a few others. 



Salmonidce. The fishes of this family are graceful in shape, and 



I'iy. 378. -Adult Salmon. 



have the body clothed in scales ; they have two dorsals, the first 

 with soft rays, followed by a second, which is smaller, formed without 

 rays, and adipose that is, formed simply of a skin filled with fatty 

 matter, unsupported by osseous rays. They inhabit the seas of 

 temperate and northern regions ; ascending the rivers at certain 

 seasons, and, in some instances, living exclusively in the great rivers 

 and watercourses. They are found even in the most elevated moun- 

 tain brooks. The grayling, trout, and the salmon, the type of the 

 family, belong to the group. 



The genus Salmo includes three well-known species, namely, Salmo 



