FISHES—CYPRINIDAE—PTYCHOCHEILUS VORAX. 
301 
lateral line, is dark brownish black, darker along tbe dorsal region, properly so called, than 
along tbe flanks, which assume a somewhat clouded aspect. The inferior surface of the head, 
up to the mouth, and the abdominal region, properly so called, are whitish. The vertical fins 
exhibit a rather dark tint, whilst the horizontal fins are dull yellow. 
References to the figures .—Plate LXY, lower figure, represents Ptychocheilus rapax, somewhat 
reduced in size. The upper left figure is a dorsal scale. The middle figure, a scale from the 
lateral line. The upper right figure, a scale from the abdominal region. 
List of specimens. 
Catal. 
No. 
Cor. No. 
of teeth. 
No. of 
spec. 
Age. 
Locality. 
When 
collected. 
Whence obtained. 
Nature of 
specimen. 
Collected by— 
205 
2758 
i 
Adult. 
Monterey, Cal. 
1853 
Lt. W. P. Trowbridge... 
Alcoholic. 
Lt. Trowbridge. 
4. PTYCHOCHEILUS VORAX, G-rd. 
Spec. Char. —Body of moderate length, rather deep upon its middle, and very much tapering posteriorly. Peduncle of the 
tail very slender. Head small, contained nearly [five times in the total length. Posterior extremity of maxillar bone extending 
to a vertical line drawn across the anterior rim of the orbit. Eye moderate; its diameter entering about six times and a half in 
the length of the side of the head. Anterior margin of dorsal fin somewhat nearer the insertion of the caudal than the extremity 
of the snout. Bluish grey above; whitish beneath. 
Syn .—Ptychocheilus vorax, Grd. in Proc. Acad. Nat. Sc. Philad. VHt, 1856, 209. 
The head is also depressed in this species, hut it is much smaller, since it constitutes nearly 
the fifth of the entire length. The body is much deeper than in P. Indus. The greatest depth 
measured immediately in advance of the dorsal fin is nearly equal to the length of the head. 
The dorsal fin is not situated so far hack, whilst the ventrals are inserted more in advance of 
the dorsal. The dorsal itself is much higher, and the anal much deeper, than long ; both of 
these fins are well developed ; the anterior margin of the anal being nearer the isthmus than the 
tip of the inferior lobe of the caudal. The posterior extremities of the ventrals do not quite 
extend to the vent; their origin is nearer the extremity of the snout than the insertion of the 
caudal. The pectorals are elongated, sub-lanceolated, their extremities being nearer the insertion 
of the ventrals than in any other species so far alluded to. 
D2,9; A 2, 8 + 1 ; C 9, 1, 9, 8, 1, 10 ; V 1, 10 ; P 18. 
The scales are rather small, and very much so upon the dorsal region between the dorsal fin 
and the occiput; they are almost minute over the abdomen, between the isthmus and the ven¬ 
trals. They are but imperfectly imbricated, even along the middle of the flanks where they are 
the largest, and much longer than deep. Indeed, they appear to be longer than deep upon all 
the regions of the body. The lateral line undergoes quite a deflection along the abdominal 
region, so as to approximate the insertion of the ventrals a great deal more than the base of the 
dorsal fin. 
The upper regions are bluish grey, whilst the predominating tint beneath is whitish or 
yellowish, with a metallic reflect. The fins themselves are yellowish. 
