222 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY IV. 
Baxbel lateral, well develoi)e(l. Eye small, 5 in head. Cheeks swollen. 
Scales larger than in IS. corporaUs., not mnch crowded forward. Lateral 
line much decurved. Dorsal tin entirely behind ventrals, its last ray 
over the first ray of the anal. Fins all small. Coloration of 8. corpo- 
rails; the black dorsal spot distinct. Head ; depth 4. D. 8; A. 7 j 
scales 9-48-5 ; teeth 2, 5-4, 2. L. 4 inches. Flint Eiver, Georgia. 
(Jordan, Bull. U. S. Nat. Mus. x, 63, 1877.) 
** Insertion of dorsal tin scarcely behind ventrals ; scales nq^arly equal over the body ; 
no conspicuous black dorsal spot. (Leucosomus Heckel.) 
349< S. bullaris (Raf.) Jor. — Fall-fish; Silver Chub. 
Body oblong, robust, little compressed. Head large, convex, the 
snout bluntly conic. Mouth large, terminal, somewhat oblique, the 
lower jaw included ; premaxillary below the level of the eye, the max- 
illary barely reaching the front of the orbit. Eye moderate, rather high 
up and anterior, 4J in head. Barbel shorter than pupil, not evident in 
young specimens. Scales large, 22 in front of dorsal, not crowded an- 
teriorly. Dorsal fin slightly behind middle of body, just behind ven- 
trals. Fins moderate. Coloration brilliant; steel-blue above; sides 
and belly silvery ; males in spring with the belly and lower fins rosy or 
crimson. Head 4; depth 4. D. 8; A. 8; scales 8-45-4 ; teeth 2, 5-4, 2. 
L. 18 inches. Largest of our Eastern Cyprinidee. Abundant from 
Massachusetts to Virginia, east of the Alleghanies. 
(Cyprinus Rafinesque, Amer. Mouth. Mag. and Grit. Rev. 1817, 120: Leudsem 
argenteus and pulchellus Storer, Eept. Fish. Mass. 1839, 90 : Chiloncmus pulchellus Storer, 
Fish. Mass. 286 : Leucosomus cataractus Baird : Semoiilus rhotheus Cope, Cypr. Penn. 362 : 
Leucosomus pulchellus Gunther, vii, 268.) 
96.— SYMMETRURUS Jordan. 
(Jordan, Bull. Hayden’s Geol. Snrv. Terr, iv, 788, 1878: type Pogonichthys argyreiosus 
Girard.) 
This genus differs from Pogonichthys chiefly in the caudal fin, which 
is developed as in Semotilus and other related genera, the two lobes 
equal, and the rudimentary basal rays comiiaratively few and small. 
The presence of grinding surface on the teeth and the position of the 
barbel chiefly distinguish Symmetrurus from Semotilus. {abpperpoq^ sym- 
metrical ; on/jct, tail.) 
350. §. arg^yriosias (Girard) Jor. 
Body elongated, pretty strongly compressed. Head moderate, con- 
siderably compressed, the snout subconical. Mouth moderate, nearly 
horizontal, the lower jaw included, the maxillary reaching the front of 
