SOUTH AMERICAN NEMATOGNATHI. 131 



36. Rhamdia minutaLiitken. 



Localities: Kio Janeiro; Macacos. 



VII. PiMELODELLA geil. IIOV. 



Pseudorhamdia Steindachner (not Bleeker). 



Type, Pimelodus cristaius. 



Head entirely covered witli skin; occipital process nar- 

 row, of the same width throughout, meeting the dorsal 

 plate; fontanel prolonged backward to the occipital pro- 

 cess with a bridge across it behind the eje. 



lay 1| in head, the dorsal fin about one-third higher than long; distance be- 

 tween first dorsal and adipose fins greater than the length of the dorsal; 

 adipose fin S-Si in the length. 



Caiidal lobes short and broad, the lower one very broadly rounded, the 

 upper slightly longer and more pointed, 4-5 in the length. 



Anal rays short, more than two in head. Ventrals If in head. 



Pectoral spine depressed, short and stout, slight! j' more than one-half the 

 length of the head, with numerous straight teeth on the posterior margin to 

 near the tip, the longest about one-third the width of the spine; recurved 

 hooks on the anterior margin. 



Pores on the chin and a few minute ones on head. 



Color light chocolate; a well-defined black band along the sides, continued 

 through the eye and around the snout; numerous dark points scattered 

 over the body; a purplish area at base of dorsal; sometimes narrow vertical 

 bars along each side of the dorsal rays; caiadal dusky. 



Head 4;-^; depth 4^-5; Br. 6 or 7. D.I, 5-6; A. 12-14. 



Rhamdia petenensis Giinther. 



Pimelodus petenensis Giinther, Cat. Fish. Brit. Mas. V. 126, 1864 (Lake 

 Peten); id, Fish. Central America 393, 1866. 

 Three specimens: length .115 — .125 m. Eio Zanaleneo, Chiapas, Mexico. 



Body below the dorsal spine scarcely deeper than wide, tapering to the 

 caudal peduncle; head little wider than the body, its greatest width 1^ to 1^ 

 in its length; flattened above; the profile steep and little convex, not de- 

 curved at the snout; snout flat and broad, its width at the angle of the 

 mouth 2-2\ in the length of the head. Fontanel becoming very narrow 

 behind the eye, continued to the base of the occipital process. Occipital 

 process narrow, not reaching half way to the dorsal plate. 



Eye small, round; little nearer tip of snout than to opercular margin; 

 2-2.^ in snout, 2 in interorbital, 6-6J in head. 



Maxillary barbels reaching to end of dorsal or little beyond base of ven- 



