-flS CALIFORNIA ACADEMY OF SCIENCES. 46 



abundance by Dr. Gilbert: not yet recorded from local- 

 ities further south. 



Family ATHERINID^. 

 62. Eurystole eriarcha (Jordan & Gilbert). Plate xxxii. 



One specimen found in a rocky pool by Dr. Gilbert; 

 a second one taken by us with a seine on the sandy beach 

 just south of Mazatlan. Only these two specimens are 

 known, and the species is probably rare. This species 

 is allied to the genus Menidia rather than to Atherina. 

 It differs from the species of Menidia chiefly in the 

 extremely long anal fin and in the smallness of its dorsal, 

 which is unusually far backward. These characters have 

 been used by Jordan and Evermann to define the genus 

 Eurystole, of which this species is type. The mouth is 

 shorter than in Menidia, but its structure is exactly the 

 same. 



Head 5; depth 5; dorsal iii-i, 11 or 12, anal 1, 27; 

 scales about 48.* 



Body short, deep, much compressed; head short, deep, 

 about % longer than deep, rather broad above; opercles, 

 truncate behind, the interorbital space about equal to eye. 

 Mouth very small, terminal, very oblique, with curved 

 cleft as in Menidia; the premaxillary very short, wide 

 behind, with curved edge, slipping under the narrower 

 maxillary; the premaxillary protractile, but not much 

 movable; jaws subequal, the lower slightly included. 

 Maxillary scarcely as long as eye, not quite reaching front 

 of eye. Teeth rather large, hooked backward. Snout 

 short, 2/4 in head. Eye large, 2^ in head. Gill-rakers 

 numerous, long and slender. Scales smooth, caducous, 

 not easily counted, 21 before dorsal. Pectoral moderate, 



* Not to be exactly counted; the number (36-7) stated in our original 

 description is an error. 



