Bae MEMOIRS OF THE CARNEGIE MUSEUM 
on the posterior face of the pectoral in specimens 83 mm. long, about 20-30 
much more feeble ones in large specimens, the more distal thorns sometimes 
with a broad base and a long free outer edge; maxillary barbels reaching origin, 
or beyond tip of adipose. . ae ae .....2. eristata (Miller & Troschel). 
dd. Caudal lobes subequal, always ges the an ihe head; 18-29 thorns on the posterior 
face of the pectoral spine; maxillary barbels reaching tip of adipose or beyond 
tips of middle caudal rays; adipose fin 2.38 in the length; pectoral spine about 
equal to the dorsal spine, sometimes shorter; dorsal spine 1—1.25 in the head. 
3. steindachneri Eigenmann. 
ddd. Upper caudal lobe normally greatly prolonged, but subequal in the young, not 
much narrower than the lower lobe; maxillary barbel always extending at 
least beyond base of anal; lateral band, if present, broad; pectoral spine a little 
longer or a little shorter than the dorsal spine with a variable number of strong 
teeth on over half its posterior margin... . .4. gracilis (Cuvier & Valenciennes). 
dddd. Upper caudal lobe not produced; maxillary barbels reaching to tip of ventrals 
or to middle of anal; about 11 teeth on the pectoral spine; adipose fin 2.75-3.25 
in the lengthy ccc ae eee ee ee eee 5. avanhandave Eigenmann. 
ddddd. Upper caudal lobe not greatly produced; maxillary barbel reaching beyond tip of 
ventrals; numerous minute teeth on the pectoral spine; lateral band ill-defined. 
6. rocce Kigenmann. 
dddddd. Upper caudal lobe not prolonged beyond the lower; maxillary barbels reaching 
origin of ventrals; pectoral spine smooth in front, with about nine thorns on 
the inner margin, the largest a little more than half the greatest width of the 
spine. No lateral band.. se te As iS aca Oe eee ..7. puruensis Fowler. 
cece. Pectoral spine smooth or but slightly ee neha upper Cr lobe prolonged; 
maxillary barbels reaching anal; lateral band narrow, well defined; dorsal spine equals 
pectoral spines: <2 svc. ces Bes eee oe eo oe ee eee 8. buckleyi (Boulenger). 
bb. Adipose fin 3 or more than 3 in the length. (See also number 3). 
e. Dorsal spine not produced into a filament. 
f. Pectoral spine with thorns along all but the very tip of the posterior margin; inter- 
orbital three-fourths as wide as eye. 
g. Maxillary barbel extending to the origin of the adipose fin, nearly to tip of ventral; 
pectoral spine equals length of head; eye 4 in the head, interorbital 5 
9. pectinifera Eigenmann & Eigenmann. 
gg. Maxillary barbel extending beyond base of anal; pectoral spine much shorter 
than head; eye 3.33 in the head, interorbital 5.5; inner pectoral thorns large; 
9 narrow dark band.-ee 7226s eee eee eee 10. hasemani Eigenmann. 
ggg. Maxillary barbel extending to end of the adipose; pectoral spine minutely serrate 
within and! without:..- - 54 0e6. eee eee leer 11. cyanostigma Cope. 
ff. Pectoral spine with 18 or fewer teeth, except in the very old. 
h. Wye large, 2.5 in the head; interorbital much smaller than the eye, 5.5 in the 
head; lower caudal lobe much the longer; pectoral spine but little shorter than 
the head; maxillary barbel reaching origin or end of base of anal. 
12. megalops Kigenmann. 
hh. Eye smaller, more than 3 in the head. 
i. D. 1.7; pectoral spine reaching ventrals, which reach to the anal. 
13. brasiliensis Steindachner. 
