Family XIV. Atherinid^e. 



179 



FlG. 60. CHIROSTOMA LUCIUS Boulenger. 

 No. 6159 (Chirostoma crystallinum J. & S.), Leland Stanford Jr. University. 



anterior margin of orbit ; pectoral 1 ^ in head ; ventral 2^ ; base of anal 

 1^ in head; scales large, a few at nape and pectoral region reduced, 

 the edges of all slightly crenate; scales between dorsal fins very large; 

 gill rakers long and slender, 27 on first gill arch. 



Color light silvery, translucent; a dark lateral silvery band; scales 

 on upper part of body with few dark dots. Length about 10 inches. 



Known at present only from Lago de Chapala and its environs. 



168. Chirostoma lermas Jordan & Snyder. 



Chirostoma lerma Jordan & Snyder, Bull. U. S. Fish Comm., 1900, 

 142, fig. 19; Lago de Chapala: Jordan & Evermann, Bull. 47, 

 U. S. Nat. Mus., 1900, 3163: Meek, Field Col. Mus. Pub. 65, 

 1902, 116; La Palma; Ocotlan. 



Basin of the Rio Lerma. 



Fig. 61. Chirostoma lerm/e Jordan tesuyder. 

 No. 6159, Leland Stanford Jr. University. 



Head 3^, depth 5^; D. iv or v-10 to 12; A. 19 to 22; scales 18-5O. 

 Body elongate, slender, not much compressed; snout long and pointed ; 

 mouth large, the lower jaw slightly projecting; mandible 2-^ in head; 

 teeth large and strong, in definite rows: the larger teeth on the inner 

 row of the upper jaw and the outer row of the lower; origin of dorsal 

 fin midway between base of caudal fin and eye ; pectoral 1 % in head ; 

 ventral 3 ; scales with crenate edges, those in region of nape and pec- 

 toral fin much reduced. 



Color light silvery, a dark silvery lateral band; few punctulations 

 on scales on dorsal region. Length about 12 inches. 



This species is easily recognized on account of its strong dentition. 

 Known only from Lago de Chapala. 



