1913.] NATURAL SCIENCES OF PHILADELPHIA. 559 



from frontals to occipital process, and latter siiort, narrowly tri- 

 angular. 



Gill-opening extends forward about opposite front edge of pupil. 

 Rakers about 7+10?, slender, lanceolate, much less than filaments, 

 and latter about | of eye. Isthmus narrowly constricted, surface 

 convex. Branchiostegals rather large, subequal. 



Scaler moderately small, disposed in longitudinal series parallel 

 with 1. 1., each well exposed, cycloid, and of mostly uniform size. 

 Along base of anal on trunk scales become smaller, and along base 

 of anal its entire length a series of scales, which larger anteriorly and 

 diminishing posteriorly. Caudal base scaled, and lobes of fin also 

 covered with small scales over greater portions. Free pointed 

 axillary scaly flap to ventral j length of fin. L. 1. complete, slightly 

 decurved till f in greatest body depth, extending a little low along 

 side of caudal peduncle 'till reaching caudal base medianly. Tubes 

 simple, extend over first half of scale at least. 



Dorsal origin midway between snout tip and caudal base, first 

 branched ray longest, with depressed fin extending half way to 

 caudal base. Adipose fin slender, about 1| in eye, its origin about 

 last y in space between dorsal origin and caudal base. Caudal well 

 forked, lobes pointed, similar, equal. Anal inserted well forward, 

 nearly midway between centre of eye and caudal base, first branched 

 ray longest and with anterior rays elevated slightly, though not 

 forming distinct lobe, and base long and straight. Pectoral low, 

 upper rays longest, pointed, and depressed fin extends back slightly 

 beyond ventral base. Ventral inserted well before dorsal, reaches 

 anal. Vent close before anal. 



Color pale brownish generally. Back and trunk above anal 

 finely dotted with, dull or pale dusky. Median pale lateral streak 

 from eye to caudal base, less than eye diameter in width. Shoulder 

 with large pale area, within which vertical, narrow, dusky streak 

 about equal to eye diameter. A narrow pale dusky vertebral lateral 

 streak posteriorly forms upper boundary of silvery lateral streak. 

 Fins all pale or grayish. No caudal blotch. Head brownish above, 

 silvered or whitish on sides and below. Iris silvery with dusky ver- 

 tical streak. Teeth pale. 

 Length 35 mm. 



Type, No. 39,293, A. N. S. P. Tributary of the Madeira River 

 near Porto Velho, Brazil. January-February, 1913. Edgar A. 

 Smith. 



Also, Nos. 39,294 to 39,298, A. N. S. P., paratypes, same data. 



