FAMILY V. CYPRINID.E. 43 



Rio Grande to the Rio Sabinal in Texas. 



Head 4; depth 4^; D. 8; A. 7 ; scales 46. Head short and blunt, 

 with broad, projecting snout. 



Color grayish above, whitish below; sides more or less marmorate; 

 a black patch at base of caudal fin and one on the dorsal. 



A little-known species. 



Subfamily Chondrostomatinse. 



15. Xystrosus Jordan & Snyder. 



EL POPOCHE. 



Xystrosus Jordan & Snyder, Bull. U. S. Fish Com., 1889, 123. 

 (Type, Xystrosus popoche Jordan & Snyder.) 



Body elongate, compressed; interorbital space low and flat; 

 mouth terminal, very oblique, jaws about equal; premaxillary pro- 

 tractile; no barbels; no pseudobranchiae ; gill rakers very long and 

 slender, about 66 on first gill arch; teeth 4-4, hooked, with developed 

 grinding surface; alimentary canal about twice as long as body, 

 peritoneum dusky. 



35. Xystrosus popoche Jordan & Snyder. POPOCHE. 



Xystrosus popoche Jordan & Snyder, Bull. U. S. Nat. Mus., 1900, 

 123; Lago de Chapala, Ocotlan, Jalisco: Jordan & Evermann, 

 Bull. 47, U. S. Nat. Mus., 1902, 3142; Meek, Field Col. Mus. 

 Pub. 65, 1902, 85; Ocotlan; La Palma. 

 Basin of the Rio Lerma. 



FlG. 7. XYSTROSUS POPOCHE Jordan & Snyder. 

 No. 61^1, Leland Stanford Jr. University. 



Head 3%; depth 4^; D. 8; A. 7; scales 15-61-7. Body rather 

 robust, compressed; head large, flattish above, interorbital width 

 2\ in head; snout pointed, 4 in head; mouth large, very oblique, 

 end of maxillary reaching vertical from anterior margin of orbit; 

 diameter of eye 4 to 4^ m head; origin of dorsal midway between 



