CHUB. 863 



Diagnosis. — From other large chubs with a barbel, this species may be 

 known by the presence of two teeth in the lesser row in the pharyngeals. 



Habits. — This species has thus far ofaly been recorded from the Upper 

 Lakes. It is probably not abundant in Lake Erie, and does not, so far as 

 is known, ascend the streams. 



A closely related species (Couesius dissimilis), with the mouth larger 

 and somewhat oblique, occurs in the Upper Lakes. 



Genus 42. SEMOTILUS, Rafinesqne. 



Semotilus, Eafinkequb, loh. Oh., 1820, 49. 

 Leucosomus, Hkckbl, Rnssegger's ReJBe, 1843, i, 1042. 

 Cheilonemua, Baird, Storei's, Fish. Mass. 1855, 288. 



Type, Semotilus, Raf = Cyprlnus corporalie, Mit. 



Etymology, sema, banner, i.e., dorsal fin ; iilus, supposed by Rafineeqae to mean 

 spotted. 



Body robust ; month terminal, the upper jaw protractile ; a small barbel on the maxil- 

 lary just above its end ; intestinal canal short ; teeth 2, 5-4, 2, hooked, without mastica- 

 tory surface; scales moderate ; lateral line continuous; dorsal more or less posterior to 

 ventrals ; anal basis short ; species of large size. This genus diifers from Telestes in the 

 presence of a maxillary barbel ; and from the European genus Gobio in the presence of 

 but two, instead of three, teeth in the lesser row. 



But three or four species are known, divisible into two well marked subgenera. 



Leucosomus. — Scales rather large, not crowded anteriorly ; dorsal nearly over ventrals 

 ■without black spot at its base. 



Semotilus. — Scales small, smaller and crowded anteriorly ; dorsal well behind ventrals 

 with a black spot at its base in front. 



The single representative -of XeMcoso»n««, Stmotilm buUaria (Raf.) Jor., the great Chub 

 or Fall fish of Pennsylvania and the Eastern. States may perhaps occur in the eastern 

 part of Ohio. This species is much the largest of the eastern Cyprinidce, and may be 

 known from S. corporalis, by the absence of the black dorsal spot, and by the other 

 characters noticed above. In the young of both species the barbel is usually too small to 

 be appreciated. 



84. Semotilus coepoealis (Mitchell) Putnam. 



Chub ; Horned Dace ; Creek Cliub ; Smaller Fall-flsh. 



Ciiprinus corporalis, Mitchill, Am. Monthly Mag., ii, 1817, 289, and 1818, 324. 



Zeuciscus corporalis, DeKay, Fishes N. Y., 1842, 213. 



Semotilus corporalis, Potnam, Bull, M. d. Z., 1863, 8 ; in Storer's Fishes Mass., 256.— Cope 



Gyp. Penn., 362, 1866 ; Proc. Phil. Ac. Sci., 1865, 85 ; Hayden's Geol. Surv. Terr. 



1870, 442, and 1871, 472.— Abbott, Am. Nat., April, 1870, 12.— Joedan, Ind. Geol. 



Surv., 1874, 223 ; Bull. Bnflf. Soc. Nat. Hist., 1876, 94 ; Man. Vert., 1876, 278.— Qoode 



Bull. U. S. Mus., vi, 1876, 64 ; and of most late U. S. writers. 

 Leucosomus corporalis, Gunther, Cat. Fishes, vii, 269. 

 Cyprinus atromaculatus, Mitchill, Am. Monthly Mag., ii, 1817, 324. 

 Leudscvs atromaculatus, DbKay, Fishes N. Y., 1842, 210.— Stoker, Synopsis, 1846, 409. 



