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bulletin of the bureau of fisheries. 
mature at about 2 % pounds, and growing to the weight of 8 to 12 pounds in Lake Superior. These 
very large whitefish are known as bowbacks. The species is one of the most valuable of all of our food 
fishes. It is probably the only large whitefish native to the Great Lakes system, Lake Erie excepted. 
In Jordan & Evermann’s Fishes of North and Middle America, the upper lakes were supposed 
to be inhabited also by the Erie whitefish, and on this supposition the name clupeijormis was retained 
for the latter, while the present species was called Coregonus labradoricus . There is very little differ- 
ence between these two species, if species they really are. In general, Coregonus clupeajormis can be 
told at once by its more elongate, more compressed and more symmetrical body, deepest at the dorsal 
fin, and scarcely elevated at the nape, by its dark and streaked back, and by its longer pectorals, which 
reach more than halfway to ventrals. The flesh of the Lake Erie fish is fatter and softer. 
The whitefishes from the basin of Lake Winnipeg, or Manitoba whitefish, show the general traits 
of Coregonus clupeajormis. In general, however, these are more robust, with larger head, deeper body, 
and longer fins. The caudal peduncle is deeper than long (the gillrakers are mutilated in all our speci- 
mens). Those from the dark or “muskeeg” water are unusually dark, with dark streaks above and 
black fins. Those from the milky waters of Lake Winnipeg (about the mouth of the Red River of the 
North) are all very pale, as pale as the whitefish of Lake Erie. As the water of Lake Erie is similarly 
milky, discolored by muddy, clay-bottomed streams, it is a question whether this feature of coloration 
is really a specific character. Perhaps Coregonus albus, as well as this Manitoba form, may be “onto- 
genetic species,” or forms dependent on the food and the character of the water. Of the Manitoba 
form of Coregonus clupeajormis we have examined hundreds of examples and have preserved examples 
from Rainy Lake at Rainier, Lake of the Woods at Warroad, Lake Winnipeg at Fort Alexander, Lake 
Playgreen, and Lake Waubegon at Oxdrift. 
We figure the example from Rainy Lake. 
The following description of Coregonus clupeajormis is taken from numerous specimens, mostly 
from Lake Superior: 
Head, 4.5 to 5 in body length to base of caudal; body depth 3.5 to 4; eye 4.5 to 5.5 in head; snout 
3.5 to 4.5; maxillary to tip of snout 3 to 4; interorbital space 3 to 3.8; caudal peduncle length from last 
rays of anal to first of caudal 1.8 to 2.5 in head, its least depth 2 to 2.5, but usually less than its length; 
dorsal 10 to 12 (fully developed rays); anal 10 to 14; scales 72 to 86 (usually over 75), between occiput 
and insertion of dorsal 30 to 34; branchiostegals 9 or 10; gillrakers 9 to 11 + 16 to 18 (25 to 28 in all) 
on first gill-arch. 
Body moderately elongate, increasing considerably in depth with age, deepest under dorsal; com- 
pressed, its width about 2.5 in its depth; dorsal profile sometimes arched from occiput to insertion of 
dorsal fin, sloping gradually to caudal peduncle, the latter deep, nearly as deep as long, sometimes 
deeper than long, compressed strongly; head small, conic, square at tip, premaxillaries directed back- 
ward so as to place mouth on lower side of projecting snout; lower jaw included, mandible reaching to 
midway between pupil and hind margin of eye, about 2.6 in head; maxillary broad and short, extending 
to anterior margin of eye, supplementaries broad, short, not as broad as long; distance from snout to 
occiput about 2 in distance from occiput to insertion of dorsal; teeth on tongue only, very minute, barely 
visible, except when dried. 
Origin of dorsal about midway between snout and base of caudal; moderate in height, between 0.8 
and the whole of the head length, almost always greater than distance from snout to occiput, its base 
1.66 in head; adipose moderate or rather large, from insertion to free end contained about 2 to 3 in head; 
pectorals and ventrals equal to longest dorsal rays in length (former reaching over halfway to vent in 
forms from Lake of the Woods, Rainy Lake, and Lake Waubegon) ; anal low, its longest ray 1.66 in head, 
its base 1.75 or 2. Lateral line straight, scales moderately large. 
Color in spirits pale, darker above, always showing more or less distinct streaks along the rows of 
scales; vertical, pectoral, and ventral fins usually colorless, save for dark margin of dorsal and caudal, 
although others are sometimes dusky. 
