ANNOTATED LIST OF THE SPECIES 101 
Pectorals reaching middle of dorsal, dorsal beyond base of ventral, ventral 
to the middle point between the anus and anal fin, end of anal not to end of adipose, 
caudal bifureated more than half its length. 
Eye 4 in head; in interorbital space 1.2-1.5; 1.4-1.5 in the snout; width of head 
in its length 1.6: mouth 2.4-2.7 in the length of the head; maxillary barbels 
reaching to the adipose; outer mental barbels not nearly to ventrals; inner mental 
to pectorals. 
Color darker than other species, nearly black on head to light brown below. 
Blue-black line from opercle along lateral line to middle caudal rays. 
Name in allusion to its mountainous habitat. 
40. PIMELODELLA PERUANA Eigenmann and Myers, sp. nov. 
Plate Tie tigs 75 
15868, 1, 52 mm., type, Inahuaya, Rio Ucayali; also paratype from same locality, very minute, 
Allen, August 22, 1920. 
Allied to P. transitoria, P. hartii, and P. meeki. 
Head 4.66 in length to basal of caudal; adipose 4.25 in the same, reaching just 
past vertical of tip of appressed anal fin. Distance from snout to dorsal 3 in length 
to base of caudal. Eye 4.16 in head length; interorbital 4.5 in same; width of head 
somewhat greater than snout plus eye; snout equals 4 of postorbital part of head; 
width of occipital process 3 in its length. 
Anterior border of pectoral spine with three weak serrations near the end, and 
numerous very evident rugosities near the basal part; posterior border with ten 
strong thorns, the first being proximal of the third serration of the anterior border; 
pectoral spine equals head less opercle, slightly longer than the dorsal spine; the 
latter not attenuated. 
Maxillary barbels extending past tip of ventrals, but not quite reaching to 
anal fin. 
Dorsal I, 6; A. I, 12; no mucous pores on head; caudal lobes equal, 1.25 in the 
length of the head. 
Coloration silvery, with a darkish lateral-line streak and a humeral spot; 
supraoccipital dark; dorsal plain. 
41. PIMELODELLA CYANOSTIGMA (Cope) 
Rhamdia cyanostigma Cope, 1870, Proc. Amer. Phil. Soc., XI, 569, Pebas; 
EKigenmann and Higenmann, 1890, Oce. Papers Cal. Acad. Sci., I, 164. 
Pimelodus cyanostigma Cope, 1878, Proc. Amer. Phil. Soc., XVII, 675; 
Higenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 388. 
Pimelodella cyanostigma Fowler, 1915, Proc. Acad. Nat. Sci. Phila., 218; 
Eigenmann, 1917, Mem. Carnegie Mus., VII, 242. 
Known only from the types from Pebas, in the Philadelphia Academy collec- 
tions. May bea Rhamdia, inasmuch as the pectoral spines are broken off. Native 
helpers must be watched carefully to forestall this type of mutilation, when collect- 
