THE WHITEFISHES OF NORTH AMERICA. 



291 



marks usually seen in the young of most Salmonidce, but our specimens 

 of coulterii, all of which are young fish, show no traces of parr marks. 

 This species was described from the Kicking Horse liiver at Field, 

 British Columbia, where more than a hundred specimens were obtained 

 by Dr. Eigenmann, in 1892, at an elevation of 4,050 feet. One specimen 

 was also secured by him from Kicking Horse River at Golden, British 

 Columbia. It has not been obtained by any other collector. It does 

 not appear to attain any considerable size or to be of any commercial 

 importance. The largest specimens yet collected do not exceed 8 inches 

 in length. The following table gives comparative measurements of 

 seven individuals examined by us: 



Table of comparative measurements of specimens of Coulter's whitefish ( C. coulterii). 



2. Coregonus williamsoni Girard. 

 Rocky Mountain Whitefish; Mountain Herring. 



Coregonus williamsoni Girard, Proc. Ac. Nat. Sci. Phila. 1856, 136, Des Chutes River 



Oregon. 

 Coregonus couesii Milner, Rept. U. 8. Fish Coruni. 1872-73 (1874), 88, Chief Mountain 



Lake, Montana. (Type, No. 14146.) 



Description. — Head, 4 £ to 5; depth, 4 to 5; eye, 4 to 5 (much larger 

 in young); snout, about 4; maxillary, 4; mandible, 2^. D. 11 to 14; 

 A. 11 to 13. Scales, 9 or 10-78 to 87-8; gillrakers, 7 to + 14 or 15, very 

 short. Body moderately long, back gently elevated, the curve from 

 middle of head to dorsal tin quite evenly convex. Head short, conic; 

 snout gently decurved, pointed; mouth small, maxillary short and 

 broad, scarcely reaching pupil, its direction nearly horizontal in the 

 closed mouth; lower jaw included, the mandible short. Mouth very 

 low; entirely below level of eye. Distance from tip of snout to occiput 

 If in distance from occiput to origin of dorsal (in. Caudal peduncle 

 rather stout; its least depth about 2| in head. Fins moderate; base 

 of dorsal equal to height of fin, If in head; origin of dorsal usually 

 equally distant between tip of snout and posterior edge of adipose fin; 

 adipose fin unusually large; anal base l.\ in height of fin or about 2 in 

 head; pectoral rather short, 1A in head; ventral still shorter, If in 

 head; caudal well forked, the lobes about equal to length of head. 



