FISHES—CYPRINIDAE—SEMOTILUS SPECIOSUS. 
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SEMOTILUS, Rafin. 
Gen. Char. —Head sub-conical; jaws equal or else even anteriorly ; gape of mouth slightly oblique upwards. The mouth 
itself being large, surrounded with soft lips. The isthmus is rather narrow. The insertion of the ventrals is situated in 
advance of the anterior margin of the dorsal fin, which is higher than long. The caudal is furcated. The scales are of 
moderate size. The pharyngeal bones are narrow, very slightly expanded upon the upper half of their curve. The teeth are 
of the voratorial kind, of the hooked type without grinding surface, stoutish, moderately hooked and disposed upon a double 
row in the following manner: 2 j 5—5 | 2; sometimes 2 | 4—5 | 2. Generally speaking, a black or brown spot may be 
observed at the base of the anterior margin of the dorsal fin. 
Syn. — Semotilus, Rafin. Ichth. Ohiens. 1820, 86.— Grd. in Proc. Acad. Nat. Sc. Philad'. VIII, 1856, 203 
The genus Semotilus , although imperfectly characterized hy its author, gives no room for 
doubt as to the species he intended to include in it. Semotilus dorsalis and Semotilus cephalus 
are both well known species. S. diplemia, on the other hand, does not come under this head. 
On the other hand, Cyprinus atromaculatus of Mitchill, of the northern and eastern States, 
belongs to it.—(See Proc. Acad. Nat. Sc. Philad. VIII, 1856, 204.) 
SEMOTILUS SPECIOSUS, Grd. 
Plate LXI, Figs. 11 — 15. 
Spec. Char.— Body elongated, sub-fusiform in its outlines. Head constituting the fourth of the total length, the furcated 
portion of the caudal excluded. Snout sub-conical ; gape of the mouth oblique ; posterior extremity of maxillar bone extending 
to a vertical line drawn at the anterior rim of the pupil. Eye moderate size, sub-circular ; its diameter entering five times in 
the length of the side of the head. Anterior margin of dorsal fin nearer the extremity of the snout than the tip of the caudal. 
Insertion of ventrals nearer the isthmus than the base of the caudal. Anal fin much deeper than long. Reddish brown above ; 
yellowish or whitish beneath. Dorsal and caudal fin provided with a black spot at their base. 
Syn. — Semotilus speciosus, Grd. in Proc. Acad. Nat. Sc. Philad. VIII, 1856, 204. 
A graceful and slender fish, subfusiform in its outline, the head, which is conical and tapering 
forwards, constitutes exactly the fourth of the entire length, if we exclude the furcated portion 
of the caudal fin. The ventrals are situated somewhat more anteriorly than in S. atromaculatus. 
The upper edge of the dorsal as well as the inferior edge of the anal are sub-convex or rounded 
off. The anterior margin of the anal is nearer the extremity of the caudal than the isthmus. 
The ventrals are small, posteriorly rounded off when expanded ; their tips, when brought 
backwards, not extending as far as the vent. The pectorals are moderate sized, sub-lanceolated, 
and far from reaching the origin of the ventrals with their extremities. 
D 1, 8 + 1 ; A 2, 8 + 1 ; C 4, 1, 9, 8, 1, 5 ; V 1, 8 ; P 15. 
The scales of the dorsal region in advance of the dorsal fin are quite small; those on the 
thoracic region are likewise smaller than posteriorly along the sides of the tail. They are 
longer than deep, except in the lateral line, sub-elliptical in their outline, sub-truncated 
anteriorly, with radiating grooves upon their posterior section only. 
The dorsal region is reddish brown, whilst the abdominal region exhibits a yellowish or 
whitish tint. A dark blackish, somewhat metallic, streak may he observed along the middle of 
the flanks, terminating at the base of the caudal into a jet black spot. A similar spot exists at 
the anterior edge of the dorsal fin near its base. The other fins are unicolor, all being of a 
greyish olive or of a light yellow. 
References to the figures. —Plate LXI, fig. 11, represents Semotilus speciosus, size of life. 
Fig. 12, a section of the body taken across the line of greatest depth. Fig. 13, a dorsal scale. 
Fig. 14, a scale from the lateral line. Fig. 15, a scale from the abdominal region. 
