186 PROCEE,DINGS OF THE NATIONAL MUSEUM vol.94 



5b, Margin of eye not free, eye small; adipose fin short, with much 

 restricted base; anal base short; postcleithral process a short 

 knob in adults, a very small spiny projection in young; bases of 

 anterior pair of barbels much farther forward than bases of 

 posterior pair. 

 60. Anterior edge of pectoral spine smooth; gill rakers 1 or 2+3 or 4; 

 predorsal plate meeting and fitting into a small notch of supra- 

 occipital process; posterior nostril about equal distance from 

 eye and anterior nostril; caudal fin forked, lobes more or les8 

 pointed; outer ends of premaxillary band of teeth with back- 

 ward-projecting angles Zungaro Bleeker 



6fc, Anterior edge of pectoral spine serrated; gill rakers 2 or 3 + 6 to 8; 

 predorsal plate meeting or not meeting supraoccipital prpcess, 

 not fitting into a notch in it; posterior nostril closer to eye than 

 anterior nostril; caudal fin more or less forked in young, lobea 

 rounded, but caudal fin usually rounded in adults; outer ends 

 of premaxillary band of teeth rounded in small ones or with 

 backward-projecting angles in adults. 



Pseudopimelodus Bleeker 

 4b. Head much longer than its width across base of pectorals; lateral ends 

 of premaxillary band of teeth rounded at all ages; caudal fin deeply 

 forked. 

 7a. Barbels bandlike, long, with membranous border and reaching to 

 anal fin; adipose fin long, 2 to 2.2 in standard length; first dorsal 

 ray more or less pungent; first pectoral ray articulate, not pun- 

 gent; supraoccipital process extending onto predorsal plate; head 

 4%, depth 6, in standard length; eye 3J4 to 5}^ in snout; head 



depressed Pinirampus Bleeker 



76. Barbels round or nearly so in cross section, filiform, sometimes a 

 little compressed basally. 

 8a. Dorsal and pectoral spines strongly pungent, very sharp-pointed; 

 predorsal plate meeting tip of supraoccipital process; anal fin 

 base short. 

 9a. Postcleithral process platelike, broad-based, triangular in 

 shape, eye contained one or more times in width of base of 

 this bone; dorsal truncate; anal emarginate; adipose base 

 about as long as anal base; bases of mental barbels not in a 

 straight line, inner pair farther forward; margin of eye dis- 

 tinctly free all way around; top of head bony. 



Pimelodus Lacep^de 

 96. Postcleithral process a spiny projection, width across its base 

 about Vz to Yi eye; dorsal and anal rounded posteriorly; 

 adipose base short to long, usually longer than anal base, 

 which is short; bases of mental barbels in a straight line or 

 nearly so; margin of eye free dorsally but more or less fused 

 ventrally; top of head covered with thin skin. 



Pimelodella Eigenmann and Eigenmann 



86. Dorsal ray flexible, not pungent; pectoral spines weakly pungent 



or flexible; predorsal plate not quite meeting supraoccipital 



process; posterior margins of dorsal and anal fins mostly 



truncate. 



10a. Postcleithral process absent; first ray of pectorals not pungent 



but flexible. 



