SALMONID.E. • 41 



largest and most curved, those of the lower jaw are next in size, then 

 follow the vomerine, palatine, and labial teeth, which are equal to each 

 other. The pharyngeal teeth are also proportionally long, and there 

 is an oblong palate, rough with very minute ones, on the isthmus which 

 unites the lower ends of the branchial arches. This space is quite 

 smooth in S. Salar, in several, if not in all the English Trouts, and 

 in S. Qiiinimt, Gairdncri, and in the imperfect specimen which I liave 

 refeiTcd to S. Scouleri. In the latter the surface of the arches is also 

 quite smooth, but in the Quiunat and Gairdneri minute rough points 

 become visible with a good eye-glass. In all the Trouts the com- 

 pressed rakers have their thin inner edges more or less strongly toothed. 

 In one of the specimens of <S. Clarkii the spinal column is nine inches 

 long, in the other six." 



