218 



PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. 56. 



Body dee])ly ovoid, well compressed, back much elevated, though 

 predoi*sal scarcely trenchant. Caudal well compressed; depth, two- 

 thirds its length. 



Head large, deep, greatly compressed, llattened sides but slightly 

 converging below. Snout convex, length two-thirds its width. Eye 

 rounded, but slightly elevated, advanced, with hind edge about 

 midway in head length. Mouth small, with short ga])e, and lower 

 jaw but very slightly protruding. Lips moderately wide. Maxillary 

 to nostrils and expansion about half of eye. Teeth uniserial, in- 

 cisor like, and end of each with slight notch. Tongue pointed and 

 free in front. Nostril simple pore, nearly opposite eye center or 





sr'yi 





V. A'* 



T-jWA^^^ 



W^^i 





Fig, 4.— Abudefduf ascensionis. 



about last third in snout. Interorbital convex. Infraorbital width 

 little less than vertical pupil diameter, edge entire; also hind pre- 

 opercle edge. 



Gill-opening forward about o])posite nostril. Rakers about 7 + 18, 

 lanceolate, but slightly shorter than filaments, which li in eye, 

 Pseudobranchiae nearly long as gill-filaments. Isthmus narrow, 

 rather slender. 



Scales large, finely ciliated, smaller along body edges, and become 

 quite crowded and minute on fin bases. Humeral scale enlarged 

 and suprascapula entire. Pointed scaly axillary ventral flap about 

 3 in fin. Cheek with four rows of scales. Each scale with about 



