46. SALMONID^E COREGONUS. 
29 ? 
g-enertilly suiiposcd. The species are highly valued for food, the flesh 
being generally pale and of fine flavor. The coloration is very uni- 
form; bluish olivaceous above; the sides and below silvery, {y-opfjr^^ 
the temples; j'covocr, angle.) 
This genus may be subdivided as follows: 
* Lower jaw iuckided; i)remaxill aides broad, placed vertically or the lower edge turned 
inward. 
t Gill-rakers short, tliickisli, few in number; preorbital broad, wider than pupil; 
maxillary sliort and rather broad, not reaching to the line of the eye; the 
small supplementary bone mostly narrow and sharply ellijitieal ; mouth very 
small (PnosoPiUM Milner) coucsi, williamsoni, quadrilatcralis, Icennicotti. 
ft Gill-rakers numerous, long, and slender; preorbital long and narrow; maxillary 
comparatively long, the supplemental bone ovate. (Cokkgonus.) 
t Tongue toothless, or nearly so ; back elevated dupeifonnis. 
tt Tongue with about three series of small teeth; body elongate, compressed. 
lahradoricus. 
ttt Tongue nearly toothless; back not elevated hoyi. 
** Lower jaw x>rojectiug; ])remaxillaries narrow, placed more or less horizontally. 
§ Body elongate, subfusiform; scales small, uniform, convex behind (Argyko- 
sowi'S Agassiz) merki, artedi, nUjripinnis. 
§^Body short, deep, comiiressed, shad-like; curve of the back similar to that 
of the belly ; scales large, larger forwards, rather closely imbricated, the 
posterior margin little convex (Allosojius Jordan) tuUibee. 
•Lower jaw included; premaxillaries broad, jilaced vertically or turned inward. 
t Gill-rakers short, thickish, few in number; preorbital broad, wider than pupil; 
maxillary short and rather broad, not reaching to the line of the eye ; the 
small supplemeutaiy bone mostly narrow and shar^ily elliptical; mouth very 
small. (Prosopium^ Milner.) 
4§45. C. CO^iaesi Milner. — Chief Moimtam White-fish. 
Ilead narrowed anteriorly, tbe snout prolonged, pig-like, protruding 
beyond the mouth. Maxillary 4 in head, barely reaching eye. Sub- 
orbital and supraorbital wider than in the other species. Depth 41 in 
length ; length of head about the same ; body therefore elongate, not 
elevmted nor much compressed. D. 12; A. 10; scales 8-88-7. Chief 
Mountain Lake, Montana, a tributary of the Saskatchawan. Yeiy close 
to the next, if really diflerent; the head and mouth larger in the single 
specimen known. 
(^liluer, Eept. U. S. Fish Com. 1872-’7.j, 83 : Prosopium eoucsi Miluer, in Jordan, Man. 
Vert. ed. 2, 3G2.) 
dSy. C. wiMiJilinaisOSiifl Girard. — Pocky Mountain White-fish. 
Body oblong, rather deeper than in C. quadrilateral is, but little com- 
pressed. Head shortish, conic, the iiroflle more abruptly decurved 
than in the others. Snout comi)ressed and somewhat pointed at tip, 
which is entirely below the level cf the eye. Maxillary short and very 
* jMilner, in Jordan Man. Vert. ed. ‘2, oGl: type C. qiiadrilatcralis Rich, (-poau-elov, 
a mask ; from the broad jireorbital.) 
