1911.] NATURAL SCIENCES OF PHILADELPHIA. 433 



to anal origin; 1 scale below 1. 1. to ventral origin; 21 to 23 predorsal 

 scales; snout 3f to 4 in head measured from upper jaw tip; eye 3| 

 to 3f; maxillary 2| to 3; interorbital 3 to 3£; gill-rakers 12 to 14 + 24 

 to 28. Snout obtuse, surface convex, length about -f its basal width. 

 Adipose eyelid moderate, pupil vertical, ellipsoid. Maxillary vertical, 

 to front eye edge. Lips rather thin. Usually, though sometimes 

 absent, a pair of inner symphyseal mandibular small conic teeth. 

 Each maxillary with 2 small teeth. Mandible slightly protruding. 

 Interorbital well convex. Suborbital length about equals postocular. 

 Gill-opening extends forward about opposite eye front. On thorax 

 median series of scales largest. Pointed free axillary pectoral and 

 ventral scaly flaps well developed. Color when fresh in rum largely 

 bright silvery-white, back and upper surface with brilliant blue-green 

 shade and largely brownish to dusky ground-color. Head brownish 

 above, silvery-white on sides. Iris deep reddish-dusky. Lips brown- 

 ish. Fins mostly olivaceous-dusky, lower pectoral rays, ventral 

 and anal paler. Length 6? inches. La Pedrita, on the Cano Uracoa. 

 February 16th, 1911. Five examples. 



This species is undoubtedly related to the specimen I have identified 

 with Chalcinus brachipomus Valenciennes, from Guiana. 8 It agrees 

 in the enlarged median lateral series of thoracic scales, and moderate 

 adipose eyelid. From Castelnau's figure of Chalcinus auritus Valen- 

 ciennes, it appears that species is also related, but it would differ in 

 the hind caudal edge being convex. Possibly the enlarged median 

 series of thoracic scales may be a character of subgeneric value, and 

 for this group of species, the subgenus Chalcinus Valenciennes, type 

 C. brachipomus Valenciennes, may be restricted. For the others the 

 subgenus Triportheus Cope, type T. flavus Cope, may be used. It is, 

 however, not possible to locate the other species satisfactorily, as they 

 have been little studied and mostly imperfectly described. C. albus 

 (Cope) and C. inagdalence Steindachner, however, seem allied with 

 Triportheus (C. angvlatus group). 



ERYTHRIXI.VK. 

 Hoplias malabarious (Bloch). 

 Three from Pedernales on January 27th. 



SILURIDuE. 

 AUCHENIPTERIN.K. 



Pseudauchenipterus guppyi Regan. 



Two specimens from Pedernales taken January 26th, and both 



Troc. Acad. Not. Sci. Phila., 1906, p. 449, fig. 43. 



