218 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY IV. 



rather small, 4| in head. Scales rather small. Lateral line somewhat 

 decurved. Twenty-four scales in front of dorsal. Fins moderate. Color 

 light olive 5 a metallic vertebral band; sides and belly silvery ; no lateral 

 band; a black spot at base of caudal; muzzle dusky; membrane of 

 upper posterior part of dorsal fin black. Head 4; depth 5^. D. 8; A. 

 8; scales 8-5C-4 ; teeth 4-4. L. 4 inches. Tennessee Eiver. 



(Cope, Journ. Acad. Nat. Sci. Phila. 1867, 227.) 



93.— COUESIUS Jordan. 



(Jordan, Bull. Hayden's Gcol. Surv. Terr, iv, 785, 1878: type Nocomis milneri Jordan = 

 Leucosomus dissimilis Grd.) 



Body elongate. Head normal, not depressed, the profile convex. 

 Mouth terminal, normal, a well-developed barbel at the posterior end 

 of the maxillary. Teeth 2, 4-4, 2, hooked, without grinding surface. 

 Scales rather small. Lateral line continuous. Dorsal fin over or 

 slightly behind ventrals; anal basis short Size rather large. (Dedi- 

 cated to Elliott Coues.) 



* Scales small, 60-70 in the course of the lateral lino. 



t About thirty scales in a transverse series from dorsal to ventrals. 



341. C squanaileaatus (Cope) Jor. 



Form stout, profile nearly plain. Muzzle not i)rominent. Mouth 

 horizontal, the maxillary not reaching the orbit. Eye rather small, 4§ 

 in head, shorter than snout. Isthmus wide. Barbel quite small. Dor- 

 sal jfin slightly in advance of ventrals, behind middle of the body. 

 Scales quite small. Olivaceous above; sides silvery; a lateral band of 

 •dark punctulations. Fins plain. Head. 31; depths. D. 8; A. 7; scales 

 17-66-14; teeth 2,4-4, 1. Henry's Fork of Green Eiver, Wyoming. 

 (Cope.) 



(Ceratichthys squamilentus Cope, Hayden's Gcol. Surv. Wyom. 1870, 442, 1872.) 

 ft About 20 scales in a transverse series from dorsal to ventrals. 



342. C. dissiiniiis (Grd.) Jor. 



Form of Semotilus corporalis, but more elongate and less compressed. 

 Head flatfish above, the snout broad, projecting over the large, oblique 

 mouth, maxillary reaching front of eye. Barbel very evident. Eyo 

 large, as long as snout, about 4 in head, 1-J in iuterorbital space. Scales 

 small, crowded forwards, those on the back smaller. Dorsal fin begin- 

 ning over last ray of ventrals. Dusky above; sides somewhat silvery; 

 an obscure dusky band through eye around snout; fins plain. Head 4:^; 



