SALMONOID FISHES OF THE GREAT LAKES. 
2 9 
from Kenosha (here figured), and from Green Bay, off Escanada. Thus far it has not been certainly 
recognized outside of Lake Michigan, the closely related L. zenithicus replacing it in Lake Superior 
and probably in Lake Huron. 
Description of Leucichthys hoyi from a cotype, a specimen 1 1 inches in length taken off Kenosha, 
Lake Michigan, sent to Doctor Jordan by Doctor Hoy, no. 119x9, Stanford University collection: 
Head about 4 in body length without caudal; body depth equal to head; length of caudal peduncle ' 
from last anal to first caudal rays 2.2 in head, depth of same 3.25; eye 4.5; snout 3.5; interorbital 
space slightly less than snout; maxillary 2.5 in head; dorsal 10 (fully developed rays); anal 11; scales 
7-72-7; branchiostegals 9; gillrakers 14+25 (gill-arch mutilated slightly, however). 
Body somewhat elongated and compressed, yet not deep; dorsal and ventral outlines similar, 
without nuchal hump or fullness; caudal peduncle long, somewhat compressed, and not deep; head 
moderately large (not as long as in L. zenithicus or L. prognathus, but larger than in L. harengus or 
L. artedi); snout rather long, blunt, because of almost vertical position of premaxillaries, which 
approach those of a true Coregonus in position; jaws subequal, the lower slightly included; maxillaries 
broad and long, extending slightly beyond vertical from center of pupil; eyes fairly large; distance 
from snout to occiput long, 0.5 distance from occiput to dorsal fin insertion. Gillrakers numerous, their 
length 0.5 eye diameter, slightly serrated on edges. Lateral line straight, scales moderate, smaller 
Fig. 14 . — Leucichthys hoyi (Gill). Cisco of Lake Michigan. (Drawn from a specimen 11.5 inches 
long, collected in Lake Michigan at Kenosha, Wis. ) 
posteriorly. Dorsal fin inserted midway between snout and base of caudal fin, low, its longest ray 
1.2 in head, its base 0.66 ray length, its margin truncate: adipose rather small; caudal widely forked ; 
anal low, its longest ray 2.6 in head, its base slightly shorter or equal; pectorals and ventrals equal in 
length, and equal to longest dorsal ray, the former not reaching quite half way to ventrals in specimen 
at hand. 
Color in spirits silvery, slightly darker above; cheeks silvery; fins colorless, save for slight black 
on edge of dorsal and caudal. 
Leucichthys zenithicus (Jordan & Evermann). Longjaw of Lake Superior. 
Argyrosomus hoyi, Milner, Rept. U. S. Fish Comm. 1872-73 (1874), p. 86, Lake Superior at Outer Island, Wisconsin; 
not of Gill, Hoy, or Jordan, and not original type. 
Argyrosomus zenithicus Jordan & Evermann, Proc. U. S. Nat. Mus.,vol. xxxvi, March 3, 1909, p. 169, fig. 3, Lake 
Superior, between Duluth and Isle Royale. 
Habitat: Lake Superior, in deep water; possibly in other lakes. 
Description of Leucichthys zenithicus, from n specimens, 8.5 to 12 inches in length, 4 from Mar- 
quette, Lake Superior, and 7 from Duluth, Lake Superior: 
Head 3.8 to 4 in length to base of caudal; depth 4 to 4.75 ; length of caudal peduncle from last anal ray 
to first caudal 2.2 to 2.5 in head, depth about 3.5; eye, 4.6; snout, 3.5; interorbital space about equal 
to snout; length of maxillary from tip of snout 2.6 in head; dorsal 10 or 11 (developed rays); anal 11 
or 12; scales 8-77 to 83-7, between occiput and origin of dorsal, 32 to 34; branchiostegals 9; gillrakers 
14 to 16+24 to 28. 
