104 FISHES OF WESTERN SOUTH AMERICA 
Peruvian Amazon to Paraguay and the Caribbean 
15758, 1, 175 mm., Rio Paranapura, Yurimaguas, Allen, November, 1920. 
Nearly straight profile, snout projecting; premaxillary band of teeth nearly 
double the width of the mandibular; dorsal spine short, not nearly reaching tip of 
last ray, conspicuous dark spot on anterior half; caudal rounded. 
45. PimeLopus cCLARIAS (Bloch) 
Silurus clarias Bloch, 1795, Ausl. Fische, pl. xxxv, figs. 1 and 2. 
Pimelodus clarias Lacépéede, 1803, Hist. Nat. Poiss., V, 93; 
Castelnau, 1855, Anim. Amér. Sud, Poiss., 34, Rio Ucayah; 
Steindachner, 1882 (1883), Denksch. KIx. Akad. Wiss. Wien, XLVI, 4, one specimen from 
the Huallaga; 
Higenmann and Higenmann, 1888, Proc. Cal. Acad. Sei., (2), I, 134; 
EHigenmann and Eigenmann, 1890, Occ. Papers Cal. Acad. Sci., I, 171, (with five subspecies 
described but unnamed); 
BKigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 388. 
Pseudorhamdia piscatrix Cope, 1870, Proc. Amer. Phil. Soc., XI, 569; 
Cope, 1872, Proc. Acad. Nat. Sci. Phila., X XIII, 262, Ambyiacu; 
Cope, 1878, Proc. Amer. Phil. Soc., XVII, 674, Peruvian Amazon. 
All South America La Plata northward, Andes eastward 
(All measurements are to end of middle caudal rays). 
15799, 4, 183-210 mm., Rio Pachitea, Allen, July, 1920. 
15800, 3, 121-150 mm., Gosulimacocha, Rio Morona, Allen, September, 1920. 
15851, 6, 157-214 mm., Iquitos, Allen, September, 1920. 
15852, 3, 177-196 mm., Lago Sanango, Yurimaguas, Allen, November, 1920. Dorsal spine longer 
than head in two. 
15853, 6, 151-186 mm., Manaos, Brazil, Allen, December, 1920. 
15854, 5, 90-127 mm., Rio Ucayali, Contamana, Allen, August, 1920. 
15855, 10, 59-92 mm., Lago Cashiboya, Allen, August, 1920. 
15856, 1, 88 mm., Rio Maranon below mouth of Pastaza, Allen, October, 1920. 
15857, 2, 73-84 mm., Rio Ucayali, near Orellana, Allen, August, 1920. 
Differing from pictus in the want of brown bars on the caudal. Anal emargi- 
nate; no conspicuous dark area on dorsal, but sides may be variously streaked or 
plain; profile steep, snout narrow and not sharply snouted; pectoral spine with 
anterior margin nearly smooth, dorsal spine weakly serrate. 
Surface feeders, often seen acting as scavengers of waste thrown from the boat- 
landings and decks of steam launches. Recognizable in their muddy habitat from 
the long, plumbeous to black barbels which break the surface-film and lie along the 
surface, moving in serpentine fashion ahead of, and about, the fish. 
46. PimeLopus LEpTrus Eigenmann and Pearson, sp. nov. 
Plate IV, fig. 3 
15858, 1, type, 175 mm., Rio Pachitea, Allen, July, 1920. 
Closely related to P. westermanni and P. altissimus, from which it differs in 
possessing a slightly larger eye, longer adipose, and longer barbels. 
