THE CYPRINODONTS. 153 
anal little nearer the latter; pectorals broad, rounded, reaching more than 
half way to the anal; caudal pedicel deep, the fin deeper than long, 
subtruncate. 
Color of specimens of four and a half inches, olive, darker on back, sil- 
very on belly and throat; fins paler, uniform, or with a darker streak around 
the base of the caudal. Three inch specimens are olive, with faint mot- 
tlings of darker, on head, body, and fins, silvery on flanks and lower surfaces, 
and dark on the chin. Individuals of two inches are olivaceous mottled with 
brownish, with silvery cheeks and a silvery band along the lateral line ; belly 
whitish. 
Compared with 0. /uéeus, in specimens of equal length, this species is 
much less rough and angular, and has a different coloration, a smaller mouth 
and less arch to the back. Lake Umayo, whence the specimens were brought, 
is said to be without an outlet, nine miles northwest of Lake Titicaca, and 
four hundred feet higher. 
Orestias albus. 
Orestias albus Val., 1839, L'Inst., VII, 118, — 1846, C. V. Poiss., XVIII, 242, pl. 537; Blkr., 1860, 
Cypr., 487; Garm., 1876, Bull. M. C. Z., III, 276. 
Orestias Mulleri (part) Gthr., 1866, Cat., VI, 330. 
B. 5; D. 14-15; A. 14-16; P. 21; Ll. 31; Ltr. 12; Vert. 13+18. 
Body short, stout, compressed, rising high above bases of pectorals, great- 
est depth about equal to length of head. Head large, about two fifths of 
the length of the body without the caudal, lateral angles blunt, crown flat 
to concave. Snout large, longer than eye, wide and deep, greatest width 
about half that of head, chin prominent. Mouth large, vertical, cleft de- 
scending little below the level of the lower edge of the eye. Teeth not 
as numerous or strong as those of 0. Cuvieri. Eye medium, two elevenths of 
the head, equal to distance from the mouth, two thirds of snout, more than 
half of the interorbital space. Scales large, rough with granulations, largest 
on head and above pectorals, fourteen to fifteen wide ones between head and 
dorsal, three rows below the eye, lacking behind the preorbital and at each 
side of the vertebral series. Base of dorsal its length from the caudal, origin 
half way from the latter to the head. Margins of pectorals, dorsal and anal 
rounded. Caudal subtruncate with angles rounded, half as long as head. 
Brown to olive, dark to light yellowish or whitish, centres of scales 
lighter; white to yellowish below. Specimens described five and a half 
20 
