46. SALMONIDiE COEEGONUS, 299 



tt Gill-raktTS numerous, long and slender; preorbitril long and narrow; niaxillaries 

 comparatively l<nig; the supplemental hone ovate, rather hroad. {Corcjonus.) 

 t Tongue toothless, or nearly so; hack elevated. 



490. C. cSupeiforniis (Mitrh.) Milner.— Cowmow White-fmh. 



Body obloug, compressed, always more or less elevated, and iK^eomiiiy; 

 notably so in the adult. Ilead comparatively small and short, the snout 

 bluntish, obliquely truncated; tip of snout on level of lower edge of 

 j)ui)il; width of preorbital less than half that of pupil. Maxillary 

 reaching past front of orbit, about i in head. Eye large, 4-5 in head. 

 Gill-rakers moderate, § diameter of eye, about 20 below the angle. 

 Color olivaceous above; sides white, but not silvery; lower fins some- 

 times dusky. Head 5; depth 3-4. D. 11; A. 11; scales 8-74-9. L. 20 

 inches. Great Lakes and northward ; the best known and most highly 

 valued of the American white-fishes. This species, like others of wide 

 distribution, is subject to considerable variationjj;, dependent on food, 

 waters, etc. Feeds on minute organisms. 



(Sahito chipeiformis Mitclijll, Amer. Month. Mag. ii, .321, 1818: Coi-ef/orum olbits Le 

 Sueur, Journ. Acad. Nat. Sci. Phila. 1, 231, 1818 : Corec/onus albiis Guntlna-, vi, 184, and 

 of authors generally: Corejoniis richardsoni Gunther, vi, 185: Coregonus sapidissiiuiis 

 Giinther, vi, 186 : Coref/onus laiior Gunther, vi, 18G : Coregonus olseyo, the " Otsego Lake 

 Cass", DeWitt Clinton Med. & Phil. Register, iii, 188.) 



tt Tongue with ahout three series of small teeth; hody elongate, compressed. 



491. C. ]lal{>radoricus Eich. — " Whiting" ; Mmquaw Pdver White finh. 



Bodj- rather elongate, compressed, the back not elevated. Head 

 rather long and slender, compressed. Mouth rather small, the jaws 

 equal, the maxillary reaching to the front of the pupil. Maxillary 

 bone broad, rather short, its supplementary i)iece ovate. jNIandible 

 reaching middle of eye. Eye large, 4^ in head. Supraorbital bone 

 narrow. Gill-rakers rather long. Bluish black above, silvery below; 

 scales with dark punctulations; fins all dusky. Dorsal fin high in 

 front, the last rays short. Head 4g ; depth 4.'5. D. 11; A. 11; scales 

 9-80-8. L. 12 inches. Great Lake region to the lakes of the Adi- 

 rondacks and White Mountains, and northeastward; generally abun- 

 dant in cold, clear lakes. 



(Eirhardsou, Fauna Bor.-Amer. iii, 203, 1838; Giinther, vi, 1~G: Coregonus neohan- 

 toniennis Prescott, Amer. Journ. Sci. Arts, xi, 342, 1851.) 



ttt Tongue nearlj" toothless ; back not elevated. 



493. C. lioyi (Gill) Jordan. — Lake Moon-eye; Cisco of Lake Michigan. 



Body rather elongate, compressed, the back somewhat elevated. 

 Head rather long, in form intermediate between Coregonus and Argyro- 



