Fishes of the IVestern North Atlantic 549 



Genus Coregonus Linnaeus 1758 



Coregoni, Linnaeus, Syst. Nat., ed. lo, I, 1758: 310, for Salmo lavaretus Linnaeus. Europe. 



Generic Synonyms: 



Tripteronotus Lacepede, Hist. Nat. Poiss., 5, 1803: 47; type and only included species, T.hautin Lacepede 



equals Salmo lavaretus Linnaeus 1758. 

 Coregonus Lacepede, Hist. Nat. Poiss., 5, 1 803 : 239; type (first mentioned) species, C. lavaretus Lacepfede equals 



Salmo lavaretus Linnaeus 1758. 



Characters. Base of Adipose fin only about half as long as base of anal. Body 

 laterally flattened, at least in most. Snout with two fleshy flaps on either side between 

 nasal openings, bluntly rounded in front. Tip of Upper jaw projecting a little beyond 

 lower jaw, its margin conspicuously sinuous. Premaxillary bones wider than long. 

 Gill rakers on first arch fewer than 28, the longest not more than a third as long as 

 lower limb of gill arch. 



Size. Coregonus often weigh up to five pounds, and occasional specimens are much 

 heavier. 



Relation to man. The Lake Whitefishes are highly esteemed market fish wherever 

 they are plentiful enough to support a commercial fishery; in the Great Lakes region 

 they are the most valuable of the foodfishes. 



Species. The genus Coregonus., as defined above, is represented in North American 

 waters by two rather sharply defined species: C. nasus (Pallas) 1776, with the gill rakers 

 shorter than the diameter of the eye (9 : 1 3), occurs in Siberia, Alaska, and Arctic 

 Canada; and C. clupeaformis^ possibly identical to C. lavaretus (Linnaeus) 1758 of 

 Europe, is the common Lake Whitefish of North America. A third form, nelsoni Bean 

 1884, also with fewer gill rakers than clupeaformis., has been reported repeatedly for 

 Alaska as a separate species, but it is only doubtfully distinguishable from C. pidschian 

 (Gmelin) 1788^ of northern Asia. Our only direct concern here is with C. clupeaformis. 



Coregonus clupeaformis Mitchill 1 8 1 8 



Lake Whitefish 



Figure 130 



Study Material. About 20 specimens, from Lake Superior, Michigan, New York, 

 New Hampshire, Maine, and the Saskatchewan River. 



Distinctive Characters. Should a coregonid of this or any other species be taken 

 in brackish or salt water, it is not likely that it would be mistaken for another fish, for 

 while its adipose fin and general make up would evidently relate it to the salmonids 

 and osmerids, its very small mouth with tiny teeth (if it has any) would mark it oflF at 

 a glance from all of these. There might be more chance of mistaking a Lake Whitefish 

 for an argentinid were it not that the argentinid's pelvic fins are posterior to the rear 



2. For a recent discussion of this matter, see especially Walters [8: 284-288). 



