NO. 5 MYERS AND WADE : ATHERINID FISHES 117 



another below; distance between caudal base and origin of 

 second dorsal 3.22-3.25 in standard length ; least depth caudal 

 peduncle 1.76-2.18 in its length; snout 3.53-3.84 in head; 



scales 55-59; depth 4.2-4.5 in standard length 



Nectarges nocturnus. 



Genus EURYSTOLE Jordan 



Eurystole Jordan, 1895, p. 418 (type by original designation Atherinella 

 eriarcha Jordan and Gilbert). 



Anal fin elongate, with a single spine and 23-31 rays, its origin in 

 advance of that of second dorsal. Dorsal fins widely separated, height of 

 the first less than the distance between the origins of the two fins. First 

 dorsal with III to V flexible spines, its origin slightly before to slightly 

 behind anal origin. Caudal fin forked. Ventral fins abdominal, farther 

 from upper angle of pectoral base than from anal origin. 



Premaxillaries dilated posteriorly, the anterior part not separated by 

 a notch from the posterior; protractile, the skin covering them separated 

 by a deep fold from that of the head. Gape strongly curved, restricted at 

 the corners of the mouth by a membrane between the jaws. Maxillary 

 reaching past vertical of front margin of orbit; it extends to below a 

 point about midway between front border of orbit and the pupil of the 

 eye. Rami of mandibles scarcely elevated. Teeth well developed, a narrow 

 band of small, pointed teeth in each jaw. Lower jaw very slightly shorter 

 than upper with mouth tightly closed. 



Sides of head and trunk scaled. Scales large, 37-41 in a lateral series 

 from above gill-opening to caudal base. Predorsal scales along mid-line of 

 back 13-16. Scales around caudal peduncle 12. Anal sheath reduced or 

 obsolete, composed of 3-8 small, modified scales on the bases of the first 

 few anterior anal rays. 



Head rather abruptly truncated posteriorly, the curve of the gill- 

 cover flat. Head and trunk moderately compressed for an Atherinid. Pre- 

 opercular angle with a small, flat, weak, closely appressed "spine." Inter- 

 orbital moderately convex. 



Eye large, its diameter greater than the shortest distance from orbital 

 rim to angle of preopercle. A distinct, thin, adipose eyelid visible in well- 

 preserved specimens. 



The wide, silvery, lateral band is abruptly constricted to a thin line 

 on the caudal peduncle and immediately broadens again to form a triangle 



