COCHLOGNATHUS.— COUESIUS. 163 



plate. The pharyngeal teeth are more strongly hooked than in Pimepludes, and the intestine is 

 shorter. 



Two species from Texas and the Eio Grande. 



1. Cochlognathus ornatus. 



Cochlognathus ornatus, Baircl & Girard, Proc. Ac. PMlad. 1854, p. 158' ; Girard, Bull.U.S. & Mex. 

 Bound. Surv., Fish. p. 46, t. 25. figs. 12-17 (1859) '' ; Jord. & Everm. Bull. U.S. Nat. Mus. 

 xlvii. 1896, p. 252'. 



Hah. Rio Grande at Brownsville ^ ^ 3_ 



19. YUHmiA, .lord. & Everm., 1896. 



Yuriria, Jord. & Everm. Bull. U.S. Nat. Mus. xlvii. 1896, p. 315. 



Body elongate, compressed. Mouth protractile, terminal, oblique ; a small barbel at the end of each 

 maxillary. Pharyngeal teeth compressed, hooked, in a single series, 4 — 4. Gill-openings separated by 

 a narrow isthmus. Scales large. Dorsal and anal fins short, the former about in the middle of the 

 length of the fish; ventral fins 10-rayed. 



A single species from the Rio Lerma System. 



1. Yuriria alta. 



Hudsonius alius, Jord. Proc. U.S. Nat. Mus. 1879, p. 301 \ 



Hybopsis alius, Jord. & Everm. Bull. U.S. Nat. Mus. xlvii. 1896, p. 321', and 1900, fig. 138' ; 

 Meek, Publ. Columbian Mus., Zool. v. 1904, p. 81 '. 



Depth of body about 4 in the length, length of head 3| to 4. Snout longer than eye, the diameter of which 

 is 44 fo 5 in the length of head ; interorbital width 3 in the length of head. Dorsal 9, with 7 branched 

 rays ; origin nearly equidistant from tip of snout and base of caudal ; longest ray | to 4 the length of 

 head ; free edge straight or slightly concave. Anal 9. Pectorals nearly or quite reaching the ventrals, 

 which are inserted below the origin of dorsal. 45 to 50 scales in a longitudinal series, S to 10 in a 

 transverse series from origin of dorsal to lateral line, 4 or 5 between lateral line and base of ventral. 

 Lateral line complete, slightly decuived. Caudal peduncle 1= to 2 as long as deep. Silvery, back 

 darker ; fins pale. 



Hab. Mexico, Eio Lerma System : 



Aguas Calientes * {Jordan, Meek), Lagos "*, Celaya * {Meek), Acambaro *, Lago 

 de Tupataro 1, Salamanca - (IFoo/'Hia?;) ; Rio Cuitzeo'*; Ojo de Agua, Michoacan 

 {Mexico Mus.). 



Here described from several specimens, measuring up to 130 mm. in total length. 



20. COUESIUS, Jord., 1878. 



Couesius, Jord. & Everm. Bull. U.S. Nat. Mus. xlvii. 1896, p. 323. 



Very similar to the preceding genus, but the body less compressed, the barbel not quite terminal, the 

 pharyngeal teeth in two series, 2, 4 — 4, 2, and the scales smaller. 



Five species from North America, including one from Northern Mexico. 



Y2 



