156 OSTAEIOPHTSI. 



B. 40 to 50 scales in a longitudinal series. 



Diameter of eye 3 to 3^ in the length of head (in specimens measuring up to 

 55 mm.) ; caudal deeply notched, the middle rays i as long as the 

 longest 12. formosus. 



Diameter of eye 4 to 5 in the length of head (in specimens measuring up to 

 80 mm.) ; caudal moderately notched, the middle rays | as long as the 

 longest 13. a;:tecus. 



1. Notropis boucardi. (Tab. XXV. figg. 4, 5.) 



Montana nitida (non Alburnus nitidus, Kirtland), Girard, Proc. Ac. Philad. 1856, p. 21 \ 



Leuciscus boucardi, Giinth. Cat. Fish. vii. p. 485 (1868) ". 



Graodus nigrotaniatus, Giinth. 1. c. ^ 



Rutihis boucardi, Jord. & Everm. Bull. U.S. Nat. Mus. xlvii. 1896, p. 247 '. 



Notropis nigrotaniatus, Jord. & Everm. t. c. p. 264 '. 



Notropia hraytoni, Jord. & Everm. 1. c. " ; Meek, Publ. Columbian Mus., Zool. v. 1904, p. 65 '. 



Xvtropis boucardi, Meek, t. c. p. 67 ". 



Depth of body .3| to 4| in the length, length of head 3| to 4k. Diameter of eye 3| to 4^ in the length of 

 head. Month little oblique ; lower jaw included within the upper ; snout obtuse. Dorsal 9, with 7 

 branched rays. Anal 8-10, with 6 to 10 branched rays. Ventrals inserted nearly below the origin of 

 dorsal, which is about equidistant from tip of snout and base of caudal. .3-5 to 39 scales in a longitudinal 

 series, 6 or 7 in a transverse series from origin of dorsal fin to lateral line, 3 or 4 between lateral line 

 and base of ventral fin. Lateral lino complete. Caudal peduncle about twice as long as deep. Usuall}' 

 a dark lateral stripe ending in a caudal spot. 



JIab. Mexico, rivers of Nuevo Leon and Tamaulipas and northern tributaries of the 

 E-io Balsas : 



Cadereita '' and Rio San Juan ^ (Meek) in Nuevo Leon ; Rio Conchos ^ and 

 Rio Soto Marina '^ {Meek) in Tamaulipas ; Yautepec ^, Cuautla '', Cuernavaca " 

 [Boucard), Atlixco ^ s, Puente de Ixtla^ [Meek), Matamoros^, Jojutla® and 

 Chietla ^. 



Here described from a series of specimens measuring up to 100 mm. in total length. 

 The examples figured are the types of Leuciscus boucardi (fig. 4) and Graodus 

 nigrotceniatus (fig. 5). 



2. Notropis orca. 



Notr'j^iis orca, Woolman, Bull. U.S. Fish. Comm. xiv. 1894, p. 56 ' ; Jord. & Everm. Bull. U.S. Nat. 

 Mus. xlvii. 1896, p. 289". 



Hah. Rio Grande at El Paso, Texas. 



3. Notropis nazas. 



Kolotropns nazas. Meek, Publ. Columbian Mus., Zool. v, 1904, p. 70, fig. 19'. 



Depth of body 4 to 4i in the length, length of head 4. Diameter of eye 3.| to 32 in the length of head. 

 Mouth little oblique; lower jaw included within tlie upper; snout rather pointed. Dorsal 9, with 7 

 branched rays. Anal 9. Ventrals inserted in advainc of tlic origin oi dorsal, wliieh is a little nearer 

 to the base of caudal than to the tip of snout. 4S to 54 scales in a longitudinal series, 9 or 10 in a 



