1911.] NATURAL SCIENCES OF PHILADELPHIA. 501 



Adipose fin moderate, inserted about midway between last dorsal 

 ray base and caudal base, fin 2\ to latter. Anal inserted opposite 

 last dorsal ray base, anterior rays elongated and second branched 

 one longest, it extending about \\ to caudal base. Caudal deeply 

 forked, lobes rather slender, pointed, tips damaged and apparently 

 equal, fin also apparently a little longer than head length. Pectoral 

 rather small, upper rays longest, fin a little falcate, not quite reaching 

 ventral. Ventral origin slightly before dorsal, fin pointed, depressi- 

 ble back a little beyond anal origin. Vent midway between ventral 

 and anal origins. 



Color when fresh in alcohol largely pale umber-brown on back 

 and upper surface, edges of scales darker. Median dorsal line also 

 somewhat dusky. Sides and lower surface of body pale to whitish, 

 and all more or less overshot with dull silvery, pale lilac in some 

 lights. Upper surface of head brownish like back, sides and lower 

 surface pale. Opercle with silvery-white reflections, and a dull 

 indigo-black blotch level with eye on its upper portion. Snout 

 entirely brownish to edge of upper lip, and mandible decidedly 

 paler like whole of lower jaw. Iris silvery-white, with grayish tinge 

 above. Transversely on back 2 broad deeper brown bands than 

 body-color, first a little narrower and at first third in predorsal region, 

 second at second third of same. An indistinct or nebulous pale 

 brown blotch at beginning of 1. 1., followed by an indistinct pale 

 gilt area to another indistinct brownish blotch within limits of second 

 dark transverse band. Behind 1. 1., though on same level, opposite 

 anal origin a distinct large rounded spot of dusky or blackish, this a 

 little larger than eye. Along sides, following median axis, a streak 

 of underlaid and rather dull silvery, though posteriorly becoming 

 quite narrowed, or about f of eye-diameter. Dorsal pale or grayish 

 basally, becoming rather dusky on outer portions. Adipose fin 

 pale grayish, edge narrowly dusky. Anal largely pale grayish, a 

 little darker marginally, and only front edge of long anterior lobe 

 slightly dusky. Caudal largely grayish like other fins, hind edges a 

 trifle dusky. Pectoral pale brownish, distally a little darker brown. 

 Ventral grayish basally, distal end of longest rays dusky slate-color. 

 Peritoneum blackish. 



Length 5 inches (caudal tips damaged). 



Type, No. 2. Collection, S. N. Rhoads. Affluent of the Chimbo 

 River near Bucay, Province of Guayas, Ecuador. July, 1911. 



Also Nos. 3 to 6, paratypes, same data. Head 3| to 3|; depth 

 2f to 2|; D. in, 9; A. usually iv, 27, sometimes iv, 25 or iv, 28; 



