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THE SALMON TEIBE 
This family forms the genus Scilmo of Linnaeus, and is 
characterized by the insertion of the mystache, or true maxillary 
bones, on each side of the snout or intermaxillaries, by a hinge ; 
by the armature of the mouth, where the jaws and border of 
the mystache are furnished with teeth, as are generally the roof 
of the mouth, with also two rows along the sides of the tongue; 
and also by the presence of two fins on the back, of which the 
hindmost is small and destitute of rays. In this last particular 
the fishes of this family stand alone among the fishes of Europe; 
but there is something like it in some Indian species; as of the 
genus Pimelodiis, which in this respect forms a link between 
the genus Salmo and the apparently very different genus Silurus. 
The armature of the mouth is less a mark of the extensive 
.family of Salmons and Trouts, as there are some aberrant sub- 
genera which have teeth less visibly in the jaws, or are altogether 
without them; but all are abdominal fishes, and within the body 
the air-bladder communicates with the gullet hy means of a 
tube, the opening of which is clearly visible. As no visible 
nerve is seen distributed to the rayless fin on the back, this 
part seems to he only possessed of common and not specific 
sensation. 
By Cuvier this extensive family is divided intr several 
genera, of which on many accounts the first stands conspicuous. 
