from the North- West Coast of America. 6 



maj be found identical. In studying tlie specimens at present 

 in the Smithsonian collection, we were obliged to confine our- 

 selves to the examination of two imperfectly dried skins of the 

 S. gairdneri, and one of the present species, which as yet are the 

 only representatives of those species contained in the collection. 

 The following differences however were found. The 8. i/runcatus 

 has the head smaller, and shorter ; tail neither so wide nor so 

 long, and more spotted ; teeth in the lower jaw more numerous, 

 but smaller ; muzzle and chin more pointed ; body posterior to 

 anal fin more slender. The lengths of the three skins were much 

 the same, those of the 8. gairdneri being slightly greater. The 

 teeth of the latter are larger and more scattered, being in one 

 specimen 9. 9. and in the other 10. 10., on the arms of the lower 

 jaw. Those of the S. truncatus have 14—16 on each side, and 

 although in line, were dispersed in a pair-like manner, i. e. 

 every other interval being greater. This pair-like disposition 

 of the teeth is not seen in the 8. gairdneri. 



From the 8. gibbsii it may be known by its greater size, and 

 much brighter colors ; proportionally smaller tail, and fewer 

 spots. The dental arrangement, however, is much the same — 

 barring the absence in the 8. gihhsii of the pair-like distribution 

 of the teeth, already spoken of. This peculiar dental arrange- 

 ment may be accidental in the specimen preserved, and has 

 therefore not been included among the specific characters of 

 the species. For the same reason, the well marked presence of 

 a double row of vomerine teeth was not included. Indeed the 

 specimens of the species of Salmonidse from the Pacific coast of 

 America, now in the Smithsonian collection, vary so much in 

 regard to the arrangement of the teeth on the vomer, that I 

 have no hesitation in rejecting, for the present, the Genus Fario 

 of Valenciennes. In this view I am noio upheld by Mr. Girard, 

 who informs me that had he received some valuable specimens 

 from the Pacific coast at an earlier day, he would have ignored 

 the Genus in his Report on the Fishes obtained on the Pacific 

 Railroad surveys. It is very probable that the arrangement 



