ZOOLOGY. 
359 
PIMELODUS AILURUS, Grd. 
Blunt-tailed Catfish. 
Plate XLIY. 
Sp. Ch. —Head large, broad and depressed, constituting the fourth of the total length. Mouth large and wide; lower jaw 
the longest; maxillar barbel extending somewhat beyond the edge of the gill aperture. Eye small and sub-elliptical. Dorsal 
and pectoral fins interiorly serrated. Base of anal fin entering about five times and a half in the total length. Caudal fin. 
somewhat emarginated posteriorly. Dark reddish brown above; whitish beneath. 
Syn.— Pimelodus ailurus, Grd. Gen. Rep. Fishes, 1858, 210. 
Several specimens of this fish were obtained from Lake Amelia, near Fort Snelling, Minnesota. 
In habits the species do not differ from their more eastern relatives. I saw none over a foot 
in length. 
PIMELODUS OLIYACEUS, Grd. 
Olive-colored Catfish. 
Plate XLI, Figs. 1—3; and Plate XLII, Yol. X. 
Sp. Ch. —Body sub-fusiform, compressed. Head very much depressed and tapering, constituting about the fifth of the 
whole length. Mouth small; upper jaw the longest. Maxillar barbel extending to the middle of the pectoral fin. Eye 
large, sub-elliptical; its diameter contained five times and a half in the length of side of head, and about twice on the 
interocular space. Dorsal spine very finely serrated posteriorly ; pectoral spine very strongly so. Caudal fin deeply fur¬ 
cated. Olive-brown above ; olive-white beneath. 
Syn. — Pimelodus olivaceus, Grd. Gen. Bep. Fishes, 1858, 211. 
Two specimens of this catfish were obtained from the waters of Milk river. It is probably 
abundant in all the turbid affluents of the upper Missouri. 
A larger species—one attaining an average weight of 12 pounds—is found in some of the 
tributary streams of the Red River of the North. Our command caught many of these at night 
with “set lines.” We found them very palatable when cooked. 
MYLOCHEILUS LATERALIS, Agass. & Pick. 
Plate XLY, Figs. 5—8. 
Sp. Ch. —Head constituting the fifth of the total length. Snout sub conical. Posterior extremity of the maxillary 
extending to a vertical line drawn across the hind nostril. Diameter of the eye entering five times and a half in the length 
of the side of the head. Anterior margin of dorsal fin equidistant between the extremity of the snout and the insertion 
of the caudal. Base of anal fin contained fourteen times in the total length. 
Syn. — Mylocheilus lateralis, Agass. & Pick, in Amer. Jour, of Sc. 2d ser. XIX, 1855, 231.— Grd. in Proc. Acad. Nat. Sc. 
Philad. VIII, 1856, 169.— Ibid. Gen. Report, Fishes, 214. 
Several of these fish were preserved. They were obtained mostly from the fresh water lakes 
near Fort Steilacoom, where they are abundant. Like the other cyprinoids of Washington 
Territory, they are of but little value as food, being bony and insipid. 
CARPIODES DAMALIS, Grd. 
Deer-nosed Carp. 
Plate XLVIII, Figs. 1 — I. 
Sp. Ch. —Head constituting the fifth part of the total length. Eye sub-circular, its diameter being contained four times 
and a half in the length of the side of the head. Angle of the mouth reaching a vertical line drawn in advance of the 
