The Blackfin Whitefish 



beds, except that they are probably in relatively deeper parts of 

 the lake. 



Head 



4i; 



depth 3^ to 4; eye 5; maxillary 2^; mandible 

 If to i|; D. 9 or 10; A. 10 to 12; scales 9-75-8; vertebrae 55; gill- 

 rakers about i5-f28. Body oblong, much compressed, back elevated, 

 the body tapering rather sharply toward the narrow caudal peduncle, 

 the adult having a slight hump as in C. cliipeifoniiis ; mouth large 

 and strong; snout straight, its tip on a level with lower edge of pupil; 

 maxillary long, reaching opposite pupil, its length j\ times its greatest 

 width; mandible very long, projecting beyond upper jaw when the 

 mouth is closed, reaching to or beyond posterior edge of the eye; 

 head rather short, deep and pointed; cranial ridges prominent; dorsal 

 rather high, the longest ray \ longer than base of fin; origin of dorsal 

 nearer tip of snout than base of caudal. Colour, sides uniformly bright 

 silvery, with pronounced bluish reflections in life; back dusky; under 

 parts pure white without silvery; above lateral line the upper and 

 lower edges of the scales finely punctulate with dark, the central 

 part unmarked, producing light longitudinal stripes extending whole 

 length of body; fins flesh-colour or pinkish in life, the dorsal and 

 caudal usually showing dusky edges; postorbital area with bright 

 golden reflection; iris golden, pupil black. 



Blackfin Whitefish 



Ai'gyrosoiniis nigripimiis Gill 



The blackfin whitefish is known certainly only from Lake 

 Michigan and Miltona Lake, Minnesota, though it has been re- 

 ported from other small deepwater lakes of Minnesota and Wis- 

 consin. It has also been reported from Lake Superior, but all 



139 



