358 FISHES OF WESTERN SOUTH AMERICA 
476. ORESTIAS CUVIERI Valenciennes 
Plate XVII, fig. 5 
Orestias cuviert Valenciennes, 1839, L’Inst., VII, 118; 
Cuvier and Valenciennes, 1846, Hist. Nat. Poiss., XVIII, 225, pl. 532, Lake Titicaca; 
Eigenmann and EKigenmann, 1891, Proc. U. S. Nat. Mus., XIV, 65; 
Garman, 1895, Mem. Mus. Comp. Zool., XIX, 147, pl. iii, fig. 11; 
Starks, 1906, Proc. U. 8S. Nat. Mus., XXX, 779; 
Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, IIT, 461; 
Evermann and Radeliffe, 1917, Bull. U. S. Nat. Mus., no. 95, 38. 
Orestias cuviertt Cope, 1877 (1878), Proc. Amer. Phil. Soc., XVIII, 44. 
Lake Titicaca 
3926 MCZ, 6, 170-190 mm., Puno, Lake Titicaca. 
3927 MCZ, 4, 172-195 mm., Puno, Lake Titicaca. 
3931 MCZ, 4, 170-180 mm., Puno, Lake Titicaca. 
3951 MCZ, 1, 160 mm., Puno, Lake Titicaca. 
1461 MCZ, 1, 175 mm., Puno, Lake Titicaca. 
31,112 MCZ, 1, 160 mm., Puno, Lake Titicaca. 
Dorsal contour convex, slightly angulate or not at all above the pectoral basis, 
flattened or moderately convex on the head, depressed before the eye by the pro- 
portions of the mouth; ventral profile almost straight; width moderate, 1.4 in the 
greatest depth, 1.7-1.8 in the length of the head. Head very long, 2.8-3.2 in the 
length without caudal, rather angular, its bones prominent, right-angled; snout long, 
broad, chin prominent, rounded. Eye large, elongated, before the middle of the 
head, 5.2-5.7 in the latter, 1.6 in the interorbital space; mouth of extreme size, the 
only one not exaggerated in Valenciennes’ figures, cleft far below the level of the 
orbit, gape exceeding interorbital space by nearly half of the latter; teeth large, 
hooked, in 2-8 broken series. 
Caudal peduncle rather long, tapering to the middle point, widening con- 
spicuously at the caudal basis. 
D. 14-15; A. 16-17; P. 18-19. 
Dorsal well back, doubtless by reason of the size of the head, its origin behind 
the middle point from occiput to caudal base, dorsal base 1.3-1.5 in the length of 
the peduncle; elevation of the dorsal moderate, its tip reaching about half way to 
the caudal basis; dorsal and anal bases slightly elevated, naked, the former exserted, 
the latter oblique; pectoral wide, moderately long, reaching barely half way to the 
vent; caudal broad, roundly truncate. The vent fleshy, slightly protuberant. 
Vertebral series of scales 22-23, with two lateral series rather complete and 
continuous, the back slightly and shallowly compressed and bordered by variable 
naked areas, lacking in two, 3926; a large preorbital plate, infraorbital scales re- 
duced to two or three; cheek and opercle scantily scaled, the former reduced to 
little more than two rows, on the latter more or less confluent; scales lacking on the 
prepectoral area, and in this species alone naked on the postpectoral to an extent just 
covered by the fin; scale-rows somewhat irregular on the largest, scales rather 
deciduous, granulations relatively sparse on forward parts, not very rough, some- 
times worn, often pearly in appearance. 
