1913. 



NATURAL SCIENCES OF PHILADELPHIA. 



533 



exposed in crescent. Interorbital broadly convex. Preorbital 

 small, narrow. Infraorbital and postorbital large, smooth, 

 completel}' cover cheek. Hind preopercle edge inclined a little 

 forward. Opercle rather large, smooth. Parietal fontanel rather 

 well developed, extends from hind frontal fusion to occiput. 



Gill-opening extends forward about opposite first third in eye. 

 Rakers about 5 + 11, slender, lanceolate, about 1^ in filaments, and 

 latter If in eye. Isthmus narrowly constricted, with groove in front 

 longitudinally and convex behind. Branchiostegals robust, rather 

 long, subequal. 



Scales moderate, all well exposed, disposed in nearly even longi- 



Fig. 8. — Aphyocharax avary Fowler. (Type. 



tudinal series, each with a few radiating striae, and of nearly uniform 

 size. On caudal base scales become little smaller than on trunk. 

 Pectoral and ventral each with pointed free axillary scaly flap, 

 former short and latter nearly | length of fin. A few scales form 

 basal series to anterior anal rays. L. 1. incomplete, only extends 

 anteriorly from shoulder nearly opposite ventral origin. Tubes 

 simple, extend over first half in scale exposures. 



Dorsal origin midway between hind nostril and caudal base, first 

 branched ray longest, and fin extends half way to caudal base. 

 Adipose fin inserted about last third in space between dorsal origin 

 and caudal base, its length little less than eye. Anal inserted behind 

 dorsal base, first branched ray longest and extends abo^ut half way 

 to caudal base. Caudal well forked, lobes pointed and subequal. 

 Pectoral pointed, upper rays longest, and fin extends | to ventral. 



