182 Bulletin 47, United States National Museum. 



concave between the orbits ; somewhat pointed in front, the snout pro- 

 jecting beyond the mouth. Width of head equal to its depth. Mouth 

 large, its width 2f in head, its opening nearly a straight line. Each jaw 

 with a strong cartilaginous sheath. Upper lip thin, with about 20 lines 

 of minute papillae. Lower lip broad, each lobe with 8 or 9 broken plicae, 

 each with minute papillae on edges. Lobes of lower lip separated by a 

 notch from which a strong frenum reaches to the chin. Fontanelle short, 

 its length about % eye. Eye 4 in head. Pectorals large, \\ length of head 

 and reaching to the sixteenth line of scales. Dorsal inserted slightly in 

 front of middle of body . Anal reaching beyond base of caudal. Caudal 

 forked. Air bladder very small, with 2 chambers. Color dark olivaceous 

 above ; a darker narrow lateral band from snout below eye straight to base 

 of caudal; the upper edge of the band obscure, the belly below the band 

 abruptly silvery ; 5 or 6 obscure dark cross bars on back and side, most 

 distinct on the dark longitudinal stripe ; base of caudal with a light band, 

 edged behind with brown. Six specimens, 3^ to 5 inches in length, col- 

 lected by Dr. Charles H. Gilbert, at some point in eastern Tennessee or 

 southwestern Virginia, thought to be from French Broad River at Wolf 

 Creek, Tennessee. It closely resembles Moxostoma cervinum, but the mouth 

 is different, (potfof, torrent; olneu, to inhabit.) 



Cotostomus rhotJiaecus, THOBURN, Proc. U. S. Nat. Mus., 1894; supposed to be from French 

 Broad River. (Type, No. 44846.) 



93. CHASMISTES, Jordan. 



Chasmisles, JORDAN, Bull. Hayden's Geol. Surv. Terr., iv, No. 2, 417, 1878, (liorws). 

 Lipomyzon, COPE, American Naturalist, January, 1881, 59, (bremrostris). 



Head large, broad and flattish above, the sides vertical. Eyes small, 

 high up, rather posterior. Mouth extremely large, terminal, the lower 

 jaw in the closed mouth being very oblique, placed at an angle of about 

 45; lower jaw very long and strong, its length more than $ length of 

 head, its tip, when the mouth is closed, about on a level with the eye ; 

 upper jaw very protractile; upper lip thin and nearly smooth. Snout 

 usually elevated above the rest of head, the premaxillary spines gen- 

 erally forming a conspicuous nose. Lower lip moderate, consisting of a 

 broad flap on each side of the mandible, in front reduced to a narrow rim, 

 the surface of the lip nearly smooth, without papillae ; nostrils large. 

 Suborbital bones narrow, but rather broader than in Catostomus ; pre- 

 orbital large ; mucous channels moderately developed ; fontanelle well 

 developed. Pharyngeal bones weaker than usual in Catostomus, the teeth 

 generally smaller. Fins moderate ; pectorals rather long ; dorsal rays 11 

 or 12 ; anal 7; anal fin high, reaching caudal ; caudal fin rather long, its 

 lobes equal. Scales moderate, large on caudal peduncle, smaller and 

 crowded anteriorly, 60 to 80 in lateral line. Sexual peculiarities not 

 marked. Coloration as in Catostomus. Air bladder in 2 parts. Size 

 rather large. Species confined to the Great Basin, (xa0fj.au, to yawn ; 

 one who yawns.) 



a. Scales moderate, 60 to 65 in the lateral line. 



6. Scales 9-63-8; dorsal rays usually 11; nose prominent. LIOBITS, 296 



66. Scales 13-66-11; dorsal rays 12. GUJUS, 2. 



