FAMILY XIV. ATHERINID^;. 173 



greater than diameter of eye; eye 3|; length of pectoral fin i> in 

 head; ventral 2^; base of anal if; caudal peduncle long and slender; 

 scales large, with entire edges, those on the nape slightly reduced in 

 size; gill rakers 4+18=22; vertebrae 23 + 20=43. 



FIG. 55. CHIROSTOMA ATTENUATUM Meek. 



No. 3631, Field Columbian Museum. 



Color light olivaceous, translucent; smallest specimens (2^ inches 

 in length) darker, more opaque; silvery band on sides narrow, incon- 

 spicuous under the pectoral fin, being widest on anterior part of the 

 caudal peduncle. Length about 4 inches. 



Common in Lago de Patzcuaro, not taken elsewhere. 



159. Chirostoma labarcx Meek. 



Chirostoma labarca Meek, Field Qol. Mus. Pub. 65, 1902, 113; La 

 Barca; La Palma. 



Basin of the Rio Lerma. 



Head 3$; depth 4%', D. iv-io; A. 20 or 21; scales 11-41. Body 

 slender, compressed; snout rather long, pointed, its length 2$ in 

 head; lower jaw slightly the longer; eye $% in head; interorbital 3; 

 mouth moderate, not very oblique, maxillary reaching slightly 

 beyond anterior margin of the eye; length of the mandible 2 l / z 

 in head; a single series of large teeth in each jaw, a few smaller 

 teeth behind these, a few near tip of jaws large and canine-like; scales 

 large, with edges entire, those on the nape very slightly reduced in 

 size; origin of spinous dorsal over vent, midway between base of 

 caudal and pupil; base of anal fin equals length of head; length of 

 pectoral fin 134 in head; ventral fins 2 in head; gill rakers 4 + 13 =17. 



Color light olivaceous, translucent; a few dark dots on margins of 

 scales on upper half of body; lateral band narrow, the portion under 

 the edge of the pectoral indistinct and made up of a few dark dots. 

 Length about 4 inches. 



Apparently not abundant, known only from a few specimens taken 

 at La Barca and La Palma. 



