28 
BULLETIN OF THE BUREAU OF FISHERIES. 
pectorals and anal margined with fainter black, the latter less; ventrals usually pale, but not always. 
This species is exceedingly close to Leucichthys nigripinnis , from which it differs by a somewhat 
shorter snout, fewer gillrakers (18+33 in our specimen of L. nigripinnis ) and the less pronounced black 
of the fins. In the measurements given by Evermann & Smith in the Report of the U. S. Commission 
of Fish and Fisheries for 1894, page 318, the gillrakers for 17 specimens of L. nigripinnis of Lake Michi- 
gan ranged from 16+30 to 19+34, whereas in our specimens (10 in number) of L. cyanopterus the 
range is from 13+24 to 14 + 27. From L. zenithicus, to which it is almost as closely related as to L. 
nigripinnis , it differs in the shorter maxillary, smaller mouth and deeper body. 
The most marked differences are in the length of the maxillary, which in L. zenithicus ranges from 
o. 10 to o. 1 1 of the body length, while in L. cyanopterus it is only 0.083 to 0.095, and in the greater depth 
of body, the former ranging between 0.21 and 0.245 (with one specimen 0.26), while the latter varied from 
0.245 to 0.28. All our specimens of L. cyanopterus were taken at Marquette, whence they were sent us 
by Mr. August J. Anderson, a prominent fish dealer at Marquette. Four specimens of L. zenithicus 
came from Marquette and 6 from near Duluth. The length of our specimens of L. cyanopterus is in 
every case greater than that of any specimen of L. zenithicus. In quality of flesh there is a marked 
difference, the L. cyanopterus taken at Marquette being very fat with thick abdominal walls, w+ile 
L. zenithicus is generally lean and with thin abdominal walls. The greater depth of L. cyanopterus 
may be due to accumulations of fat. 
Other specimens are from Duluth and from off Knife River, at the head of Lake Superior. The 
species abounds in the deep waters of the lake, its value exceeding that of the other deep-water species. 
A large specimen apparently belonging to L. cyanopterus was found in the Toronto market. Its fins 
were almost without dark markings. It must have come from Wiarton, on Georgian Bay. It is 
very unlikely that any Lake Superior fish would be mixed with these. 
Comparison of specimens 0} Leucichthys cyanopterus from Marquette , Lake Superior. 
Specimen no . . 
5242 
5228 
5246 
5243 
5248 
5247 
5244 
5240 
524s 
5249 
Length without cau- 
dal mm . . 
28s 
29s 
305 
322 
325 
330 
335 
340 
345 
345 
Dorsal rays 
10 
10 
n 
10 
1 1 
10 
1 1 
1 1 
1 1 
IO 
Anal rays 
1 1 
1 2 
1 2 
1 1 
14 
12 
1 1 
12 
1 r 
I I 
Scales 
8-79-7 
8-78-7 
8-86-7 
8-85-7 
8-82-7 
8-87-7 
8-81-8 
8-76-7 
8-83-8 
8-82-7 
Scales between occiput 
and dorsal fin 
35 
32 
35 
35 
33 
36 
32 
32 
33 
33 
Branchiostegal 
9 
9 
9 
9 
9 
9 
9 
9 
9 
9 
14+27 
9 
13 +24 
9 
14+24 
9 
13 +24 
9 
14 +27 
9 
14 +27 
9 
13 +25 
<r 
14+26 
9 
14+26 
9 
Sex 
9 
Comparative measure- 
ments:® 
Head 
0. 24 
0. 265 
0. 255 
0. 245 
0. 24 
0. 25 
0. 262 
0. 25 
0. 23 
0. 245 
Depth 
■ 25 
• 245 
. 28 
. 26 
• 27 
• 275 
. 265 
. 26 
• 25 
. 27 
Caudal peduncle — 
Length 
. 10 
• 115 
. 12 
. 1 r 
• ii 5 
. 10 
. 10 
■ ns 
. 12 
• IIS 
Depth 
• 07s 
• 07 
. 08 
. 08 
. 085 
. 08 
. 08 
• 075 
.08 
. 085 
Eye 
• 05 
■ 05 
• 054 
■ 05 
• 052 
• 052 
052 
• 05 
• 05 
. 05 
Snout 
• 07 
. 08 
• 07 
. 067 
• 07 
. 067 
• 075 
• 065 
. 065 
• 07 
Maxillary from tip of 
snout 
09 
• 095 
09 
. 087 
. 083 
• 095 
• 095 
• 09 
. 09 
. 09 
Snout to occiput 
- 17 
. 18 
. 18 
• 17 
• 165 
• 175 
. 18 
. 18 
. 165 
. 173 
Pectoral length 
• 17 
• 19 
• 17 
• 19 
• 175 
. 18 
• 185 
• 19 
• 19 
• 195 
Ventral length 
• 165 
. 16 
• 17 
. 18 
. 16 
. 18 
• 17 
• 17 
• I 7 S 
. 16 
Dorsal height 
■ 15 
• 155 
■ IS 
. 16 
• 15 
• 165 
• 15 
■ 15 
• 14 
. 14 
Adipose length 
. 065 
- 07 
. 07 
• 07 
. 06 
. 065 
. 065 
• 075 
. 062 
• 07 
Anal height 
. 10 
• 095 
. 105 
. 10 
. 10 
. 10 
. 10 
. 10 
. IO 
. 1 1 
a Measurements in hundredths of body lengths unless otherwise specified. 
Leucichthys hoyi (Gill). Cisco of Lake Michigan; Kiyi; Chub ; Mooneye Cisco. (PI. v.) 
Argyrosomus hoyi Gill Ms., in Hoy, Trans. Wis. Ac. Sci., vol. i, 1872, p. 100, Lake Michigan off Racine; no descrip- 
tion. Milner, Rept. U. S. Fish Comm, for 1872-73 (1874), p. 86; in part; no description. Jordan, Rept. Geol. 
Surv. Ind. 1875, p. 5, Racine, Wis., specimen received from Doctor Hoy. Jordan & Evermann. Fishes of North 
and Mid. Amer., pt. 1, p. 469, 1898, Racine and Kenosha. Evermann & Smith, Rept. U. S. Fish Comm. 1894, 
p. 310, pi. 22 (1896), Lake Michigan. 
Habitat: Lake Michigan, in deep water. 
This beautiful cisco is very abundant in the deep waters of Lake Michigan and is an excellent 
food fish, very delicate in flavor. We have examined specimens from Racine (Doctor Hoy’s type), 
