300 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY — IV. 
ftomus. ^loiilh rather large, teriuiual, the lower jaw evidently shorter 
than upper, even when the month is open; tip of muzzle rather bluntly 
truncate; maxillary reaching to opposite middle of pupil, about 3 in 
head; mandible extending to posterior margin of pupil. Supraorbital 
and preorbital narrow. Eye very large, 3.1 in hc'ad. Tongue with 
traces of teeth, tiill-rahers slender, about — o below the angle, i<ither 
long, nearly as long as eye. rseudobranchim very large. Fins low; 
free margin of dorsal very obli(]ue. Color bluish above, sides and be- 
low rich silvery, brighter than in any other of our Corcfjoni, much as in 
Ihjodon and Albula. Lateral line almost straight. Head 4^ ; depth 4^. 
1). 10; A. 10 ; scales 7-75-7. L. 12 inches. Deep w aters of Lake Mich- 
igan, Lake Ontario, and neighboring lakes; the smallest and hand- 
somest of our Coregoni. It is intermediate in its relations betw'ceii the 
typical Coregoni and Argyrosomm. 
(^.Irgift'o^oinits hogi (Gill, MSS.) Milner, R(?pt. U. S. I isli Com. 18/2-’73, 86, 18/ 1 ; 
Jordan, Man. Vert. ed. 2, 275.) 
** Lower .jaw projecting; premaxillaries narrow, placed more or less horizontally. 
Body elongate, snbfiisiform; scales small, uniform, convex behind. {Jnjgro- 
DoinuH Agassiz.*) 
493. C. E 2 Bvi’ki Gthr. 
Steel-bluish above, wdth many dark points; belly white; dorsal and 
caudal mostly blackish ; pectorals and ventrals tipped with black ; eye 
blackish, the iris silvery. Body rather elongate, compressed. Form 
of mouth as in C. artedi, the lower jaw' considerably projecting; max- 
illary broad, with rather broad supplemental bone, three times as long 
as wide, extending to middle of the very large eye, its length 3 in head; 
lireorbital extremely narrow. Length of mandible somew hat more than 
least depth of tail. Teeth none, or reduced to minute asperities on 
the tongue. Gill-rakers numerous, very long and slender. Dorsal 
very high, much higher than long, its last rays rapidly shortened, the 
first rays twice the length of base of fin; insertion of dorsal midway 
between snout and middle of adii)Ose fin. Caudal large, well forked; 
anal small; ventral inserted under middle of dorsal, veiy long, § length 
of head; in*ctoral the same length. Scales as in C. artedi. Head 5; 
depth 52 . Eye 3 in head. D. 11; A. 14; V. 11; scales 7-80-8. Behr- 
ing’s Sea to the north shore of Siberia, ascending rivers; lately' obtained 
by Dr. Bean in Alaska. 
{Salmo chipeoiden Pallas, Zoogr. Ro.ss. Asiat. iii, 410; not Coregonus chtpeoides La- 
c<5pedc; Gilntber, vi, 105.) 
* .tgassiz. Lake Superior, 150, oJO : type Coregonus clupciformis DcKay, not of 
Mitcliill, = C'o)T//yHU8 artedi Lc Sueur, {apyi^po?, silver; Oibpa, body.) 
