526 PROCEEDINGS OF THE ACADEMY OF [Oct., 



distance, forming narrow free fold over anterior trenchant keel of 

 isthmus at that point. 



Scales caducous, mostly fallen, narrowly imbricated, arranged 

 in even lengthwise rows, each with about 5 vertical striae, and all 

 of more or less uniform size. Dorsal and anal depressible within 

 broad basal scaly sheaths. Caudal base scaly, and each lobe with 

 small crowded scales. Pectoral with free pointed axillary scale 

 half length of fin. Similar ventral axillary scale but slightly shorter 

 than fin. 



Dorsal origin midway between snout tip and caudal base, graduated 

 down from first branched ray which longest, and tips of front rays 

 not extended far back as tips of last rays. Anal origin slightly 

 before end of dorsal base, or about midway between pectoral origin 

 and caudal base, and graduated down from first branched or longest 

 ray. Caudal well forked, pointed lobes about equal. Pectoral with 

 uppermost ray greatly elongated, extending back nearly far as end 

 of depressed ventral, or if this ray removed fin almost reaching 

 ventral. Ventral inserted little nearer pectoral than anal, reaching 

 about half way to latter. Vent close before anal. 



Color in alcohol largely whitish, sides with somewhat translucent 

 appearance. Back and upper surface of head dotted with dusky 

 under slight or pale olive ground-color. Sides of head and iris 

 bright silvery-white. Dorsal pale or grayish, dusky dots on basal- 

 scaly sheath. Caudal conspicuously dusky. Row of underlaid 

 and rather obscure pale dusky dots along base of anal. Other fins 

 whitish. Side with broad silvery-white lateral band, expanded over 

 anal and along side of caudal peduncle till wide as eye. 

 Length 3 inches. 



Type, No. 45,080, A. N. S. P. Port-of-Spain, Trinidad, British 

 West Indies. February-March, 1915. Richard M. Abbott. 



Also Nos. 45,081 and 45,082, A, N. S. P., paratypes, same data. 

 Head 3§; depth 4f to 4f ; D. iii, 12 or in, 13; A. iii, 21; scales in 

 lateral series 36 to 38 to caudal base, and 3 or 4 more on latter; 

 about 9 scales transversely between dorsal and ventral origins; 

 15 or 16 predorsal scales; snout 4| to 4^ in head; eye 4; maxillary 

 1^ to 1|; interorbital 3f to 3f ; length 2| to 3 inches. 



This species is closely related to my A. plaiyargyrea,^^ but appears 

 to differ in having the upper pectoral ray elongate and filiform, 

 more anal rays, and a narrower silvery lateral band. In the large 



"Proc. Acad. Nat. Sci. Phila., 1911, p. 210, fig. 4. ,St. Martin's, W. I. 

 Tojardo, Porto Rico. 



