FISHES — CYPRINIDAE — SEMOTILUS SPECIOSUS. 283 



SEMOTILUS, Rafin. 



Gen. Char. — Head sub-conical ; jawa 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 tlieir 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. 



Sxn.—Semotilus, Rafin. Ichth. Ohiens. 1820, 86.— Grd. in Proc. Acad. Nat. Sc. Philad. VIII, 1856, 203. 



The genus Semotilus, although imperfectly characterized by its author, gives no room for 

 doubt as to the species he intended to include in it. Semotilus dorsalis and Semotilus cepTialus 

 are both well known species. 8. diplemia, on the other hand, does not come under this head. 

 On the other hand, Cyprinus atromaoulatus of Mitchill, of the northern and eastern States, 

 belongs to it.— (See Proc. Acad. Nat. Sc. Philad. VIII, 185G, 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 tlie 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. 



SvN. — 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. airomaculatus. 

 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 be 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.— Fl-die 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. 



