PISHES-PERCI DAE—CALLIURUS MIC ROPS. 
17 
List of specimens. 
Catalogue number. 
No. of specimens. 
Locality. 
When collected. 
404 
1 
Otter creek, Arkansas- 
1851 
405 
2 
Rio Cibolo, Texas_ 
1851 
406 
4 
Mineville, Texas__ 
1853 
407 
5 
Rio Seco, Texas_ 
1853 
408 
2 
Platte river_ 
1856 
409 
4 
Rio Pecos_ 
1856 
Whence obtained. 
Original number. 
Nature of specimens. 
Collected by— 
Capts. Marcy and McClelland. 
Colonel Graham_ 
Alcoholic. 
. .do. 
Captain Marcy .... 
John H. Clark_ 
Dr. Xennerly _ 
Major Emory__ 
. .do. 
Lieutenant Whipple_-_ 
19 
_do__ 
.do. 
Captain Pope ___ 
Captain Pope__ 
5. CALLIURUS MICROPS, Grd. 
Plate IV, Figs. 5—8. 
Spec. Chae. —Mouth moderate; gape oblique upwards. Posterior extremity of maxillary extending to a vertical line drawn 
midway^between the anterior rim of the orbit and the pupil. Eye small. Insertion of ventrals situated posteriorly to the 
base of pectorals and the origin of the dorsal; their tips not reaching the vent. Scales moderate. Reddish brown above, 
with centre of scales lighter; greyish beneath. Soft portion of dofsal provided with a black patch. 
Stn .—Calliurus microps, Gkd. in Proc. Acad. Nat. Sc. Philad. November, 1857. 
This species is very characteristic, owing to the comparatively small size of its eyes and the 
reduced cleft of its mouth, to which might he added the disproportional size between the scales 
on the cheeks and those on the opercular apparatus. The posterior extremities of both the dorsal 
and anal fins do not extend as far hack as the insertion of the caudal. 
The head constitutes a little less than the third of the total length, which is exactly three 
times the greatest depth. The outline of the body is rather regularly elliptical. The edge of 
the preopercle is minutely serrated. 
The scales are higher than long ; the pectinations of their posterior margin being altogether 
obliterated. 
Br. VI: VI; D X, 11; A III, 9; C 3, 1, 8, 7, 1, 2; VI, 5; P 13. 
The extremities of the pectorals are nearly even with the tips of the ventrals, which do not 
reach the vent, situated a little way in advance of the anterior margin of the anal fin. 
The dorsal region is dark reddish brown, as well as the upper surface of the head. The sides 
of the head and flanks are of a lighter hue ; and since the middle of the scales on the latter 
region are marked with a very light spot, the sides of the body appear as if provided with 
longitudinal white stripes. The inferior region is greyish or whitish. The fins are unicolor, 
of a greyish olive; the posterior portion of the dorsal fin alone exhibiting a dark or jet black 
spot. 
References to the figures. —Plate IV, fig. 5, represents Calliurus microps , size of life. Fig. 6, 
is a scale from the dorsal region. Fig. 7, a scale from the lateral line ; and, Fig. 8, a scale 
from the abdominal region. 
3 a 
