84 PROCEEDIXGS OF UNITED STATES NATIONAL MUSEUM. 



subioferior, overlapped by the broad, bluut snout, its breadth considera- 

 ble, but the maxillary not extending far back, not to opposite the front 

 of the eye. Upper jaw protractile, covered with a fleshy lip, inside of 

 ■which is a small, straight, cartilaginous plate, similar to that on the 

 lower jaw, but much smaller and not evident externally. Lower lip 

 covered with a firm cartilaginous plate, sharp externally, the upper 

 surface being formed by its bevelled edge. The transverse width of this 

 plate is between four and five times its (longitudinal) breadth. The 

 plate extends in nearly a straight line from one angle of the mouth to 

 the other; its transverse width is contained 2^ times in the length of the 

 head. Eye rather large, 5J in head, 1| in snout, its position anterior 

 and not high up, 2;^ in interorbital space. 



Fin-rays : Dorsal 1, 10. Ventrals, 9. Anal I, 9. Dorsal long, rather 

 low, its first ray just behind the first ray of ventrals, about over the 

 middle of the latter fin, midway between the snout and the middle of 

 the base of the caudal fin ; caudal fin very long, the lobes about equal, 

 longer than the head, widely forked, the accessory rays at its base 

 very numerous and recurrent on the caudal peduncle; about eight of 

 these may be distinguished on each side of the tin. Anal fin rather 

 large ; ventrals broad, not reaching vent. Pectorals moderate, not 

 reaching two-thirds of the distance to the ventrals. 



Scales quite small, somewhat imbedded in the skin, very loosely 

 imbricated, or often scarcely imbricated at all, the exposed surfaces 

 longer than high, profusely punctate; squamation quite irregular; the 

 scales smaller on back and belly than on sides, most exposed on caudal 

 peduncle. Scales 21-85-13. Lateral line broadly decurved. 



Coloration very dark, belly paler, but nearly all parts of the body 

 studded with minute dark points. 



Teeth 5-4 (5 on the left side, 4 on the right), hooked, somewhat club- 

 shaped, with a broad masticatory surface. 



Peritoneum black ; intestines much elongate, filled in this specimen 

 with vegetable substance, apparently fine leaves and branches of a 

 Sphagnu7n\[k(^ moss. 



Length of specimen examined, one foot. 



8. MYLOCHILUS CAURINUS (Richardson) Girard. 



1836— Cyprinun (Leuciscus) caurimis Richardson, Fauna Boreali-Americana, iii, p. 304. 

 Leuciscus canrinus DeKay, Zoology N. Y. Fishes, p. '215, 1842, 

 Leuciscus canrinus Cuviek & Valenciennes, Hist. Nat. des Poissons, xvii, p. 



325, 1844. 

 Leuciscus caurinus Stoker, Synopsis Fishes N. Am. p. 159, 1846. 

 Mylochtilus caurinus Girard, Proc. Acad. Nat. Sci. Phila. p. 169, 1856. 

 Mjjlocheilus caurinus Girard, Pac. R. R. Expl. x, p. 213, pi. 46, f. 1-4, 1858. 

 Leucosomus caurinus Guntiiek, Cat. Fishes Brit. Mus. vii, p. 270, 1868. 

 Mylochilus caurinus Jordan &, Copeland, Bull. Buffalo Soc. Nat. Hist. p. 155, 1876, 



(name only). 

 Mylochilus caurinus Jordan, Catalogue Fishes, p. 427, 1878. 



