4 Descri'ptions of Several New Species of Sahnonidae^ 



yet approach eacli other in so many characters, differing only 

 in shade and intensity, — it is very difficult to give a concise and 

 striking summary of the leading characters of any one species, 

 so that by reading a short synopsis those nearly allied may be 

 readily distinguished. This difficulty is strongly felt in charac- 

 terizing the present species from several others having many 

 points in common, and when in addition to the great resem- 

 blance of typical specimens of the healthy fresh run adults, we 

 add the perplexities induced by changes in age, sex, and condi- 

 tion, confusion becomes only the worse confounded. To remedy 

 these unfortunate obstacles to success, will require years of 

 patient labor and investigation. 



The following brief diagnosis may serve to assist in distin- 

 guishing the present species from its nearest relatives found in 

 the same region. From S. quinnat Rich, it may be known by 

 the much smaller head, and rounded — not pointed — snout. The 

 smooth triangular projection extending in front of the syin- 

 physis mentis of that species is also wanting. The tail of the 

 adult S. quinnat is very deeply lunated — almost forked, that 

 of the present species is so abruptly terminated that it has 

 suggested tlie specific name applied, the end being almost 

 as abruptly truncated as if chopped off with a large knife. 

 In this respect it resembles the adult male of the Salnio trutta 

 Lin., as figured in Agassiz' Histoire Naturelle des Poissons 

 Weau douce, Planches, Livraison I. Tab. VII. 



Another difference is in the greater size and thickness of the 

 ^iS'. quinnat, which not nnfrequently attains a weight of 30 or 

 40 lbs., whereas the present fish is usually found not exceeding 

 ten or twelve pounds, and generally much less ; and its common 

 length when full grown rarely exceeds 32 inches. From the 

 S. gairdneri of Richardson (not of Girard — see Fig. LXXI. 

 Pacif. R. R. Reports, which is drawn from the young of some 

 other species), it is more difficult to be distinguished, both having 

 many characters in common. It is possible that hereafter, upon 

 accurate comparison being made with numerous specimens, they 



