Family V. Cyprinid^. 



6] 



rather heavy; snout short and rather blunt; mouth small, oblique, 

 the lower jaw included; the maxillary scarcely reaching vertical from 

 anterior margin of the eye, 3K in head; eye 5 in head; snout 34; 

 teeth 4-4; hooked, and with crenate edges; origin of dorsal fin midway 



FlG. 14. AZTECULA LERM/€ (Evermann & Coldsborouglu. 

 No. 50003, U. S. National Museum. 



between base of caudal and nostril; about 23 scales in a series be- 

 tween nape and dorsal fin; pectoral if in head; ventral 2 ; lateral line 

 decurved, not wholly complete, an occasional scale without any pore; 

 least depth of caudal peduncle 2% in head. 



Color grayish olivaceous on back and upper part of side, the scales 

 profusely covered with dark punctulations ; a broad dark plumbeous 

 lateral band ending in an indistinct black spot at base of caudal; 

 pectoral, caudal, and dorsal fins dusky; the ventrals and anal pale. 

 Length about 2% inches. 



This species is closely related to the preceding, from which it differs 

 chiefly in the more slender peduncle, the larger eye, less rounded snout 

 and coloration. Spawns late in summer. At present this species is 

 known only from Lerma, from which place a few specimens were taken 

 by me. 



53. Aztecula mexicana Meek. 



Aztecula mexicana Meek, Field Col. Mus. Pub. 65, 1902, 81; San 

 Juan del Rio. 



Basin of Rio San Juan on the Mexican Plateau. 



Head 4; depth 3^ to 4; D. 8; A. 7; scales 9-59-7. Body robust, 

 back slightly elevated, its highest point over pectoral fin and some- 

 what in advance of the dorsal; snout bluntish; mouth small, oblique, 

 terminal, lower jaw the shorter; snout 4 in head; teeth 4-4, hooked, 

 no grinding surface; interorbital area 3 in head; eye small, 4^2 in 

 head; origin of dorsal fin midway between base of caudal and the eye; 

 about 30 scales in a series between nape and dorsal fin; pectoral fins 

 short, i-3 in head; ventrals 2 in head; caudal fin rather short, forked; 



