226 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 94 



lobes are not pointed and only partially rounded, of equal length;: 

 first dorsal ray soft, equal in length to first branched ray, margin of 

 dorsal fin truncate; simple rays of anal fin graduated, the first branched 

 soft ray longest, margin of this fin truncate; paired fins with rounded 

 posterior margins; first ray of pectoral not spinous, about equal in 

 length to first branched ray; the adipose fin is long but somewhat 

 high, its total length about 4 times in the standard length, and much 

 longer than the space from rear base of dorsal to adipose origin; 

 pelvics inserted under second branched ray of dorsal; anal origin 

 about an eye diameter in advance of a vertical line through adipose 

 origin; anus a trifle closer to caudal fin base than tip of snout. 



Color. — General color blackish above, paler below, with the pale 

 caudal fin sharply contrasting with the black base of caudal fin; a 

 pale bar, sometimes obscure, across occipital and down to upper end 

 of gill openings; origin of dorsal and the area just in front blackish, 

 sometimes behind this a small, paler blotch, then at rear base of dorsal 

 the pigment is more intensive; body below dorsal fin base paler except 

 a blackish diffuse oblong blotch along lateral line; a wide pale bar 

 between dorsal across body to in front of anal, another on caudal 

 peduncle, these pale bar pigments somewhat obscure in larger speci- 

 mens ; the black bar from base of caudal fin to anal is obvious ; on the 

 smaller specimens a small pale spot occurs at origin of adipose, absent 

 on larger specimens; paired fins pale, dorsal and anal pale; snout pale; 

 front of chin and lower jaw pigmented. 



Remarks. — This new species differs from the other members of the 

 genus Cetopsorhamdia with elongate adipose fins in color, and it is the 

 only one of the species having the anal fin origin so far in advance of 

 the adipose origin. 



Named Orinoco for the river system in which it was collected. 



Genus NANNORHAMDIA Regan 



Nannorhamdia Regan, Ann. Mag. Nat. Hist., ser. 8, vol. 12, p. 467, 1913. (Type, 

 Nannorhamdia spurrelli Regan.) 



The state of preservation determines to a large extent whether the 

 rim of the orbit is free from the eye dorsally. If the eye bulges even 

 a little, the dorsal edge of the rim does not appear free; only in well- 

 preserved specimens the dorsal rim of the orbit is distinctly free and 

 then not strongly. The first ray of the dorsal fin is definitely not a 

 pungent spine. The segmentation of this ray can be seen occurring 

 nearly to its base. The pectoral spine is not a pungent spine, but if 

 the soft-rayed portion is broken oft' at the proper place a more or less 

 sharp-pointed spine can be felt and seen. The posterior half of the 

 first pectoral ray or spine is segmented nearly to its base. There are 

 usually seven gill rakers on the lower half of the first gill arch. The 

 number of fin rays varies according to the data recorded in table 7. 

 The caudal fin usually has 15 branched rays. 



