158 
b. Melanistic phase. 
Adult f (VI): Uniform brownish black. Tail deep black, narrowly 
tipped with white, and crossed by two bands of gray, which change to 
white or cream-color on the inner webs ( = C. boliviensis Burm. and C. 
puckerani Leot.). Young (VII): Similar to the above, but the feathers 
of the upper surface with narrow terminal margiues of rusty, and those 
of the crissnm with white tips. 
The black plumage described above, and upon which Cymindis bolivi¬ 
ensis of Burmeister and C. pucherani of Leotaud were based, is almost 
certainly merely a melanism of the common R. uncinatus. We have 
seen two specimens—an adult in the museum of the Boston Society of 
Natural History and a young female in the American Musum of New 
York. They agree entirely with Burmeister’s description referred to 
above, which is as follows :— 
DiAGr. — U C. fusco-nigra, remigibus rectricibusgue subtus albo-fasciatis ; 
cera pedibusque croceis; long 18 // . 
u We have of this species one specimen iu our museum, which was killed 
near Santa Cruz de la Sierra, in the woody plains of the interior of 
Bolivia. As I can find no description of this bird in the works fallen 
under my inspection, I describe it as a new species. 
“In size aud figure, entirely like the common Brazilian species Cym. 
uncinata. The bill not stronger, and of the same form, but rather longer; 
the upper mandible black, the lower mandible whitish. The sides of the 
face, from the beak to the eyes, naked, with some black bristles in a row 
from the eye to the nostrils. Iris dark brown. The whole plumage black¬ 
ish-brown, but the bases of the feathers of the vertex from the front to 
the occiput white; the nuchal feathers elongated, broad, rounded. First 
primary short, not longer than the secondaries; the second somewhat 
longer than the fifth; the third somewhat longer than the same; and 
the fourth the longest of all; every one with four or five white bands on 
the inside, of which the exterior is somewhat grayish. Secondaries of 
nearly equal size, every one with five or six whitish bands on the inside, 
which are only clear white in the middle of the plume. Tail only two 
inches longer than the wings in position, black, with two large gray 
bands on the upper side, and the same white on the under side, aud a 
similar margin at the euds of the rectrices. Legs yellow, with black 
claws, the outer toe the same length as the inner; the tarsus covered 
in front with small hexagonal scales. 
u Whole length,from the tip of thebeak to tbeend of the tail, 18 inches; 
beak, 1 inch; wing, 10 inches; tail, 7 inches; tarsus, 11 inch; middle 
claw [toej without the nail, 11 lines, the nail, 8 lines.” 
With Burmeisters description of his Cymindis boliviensis , as quoted 
above, a specimen in the collection of the Boston Society of Natural 
History;* w r hile another in the New York Museum agrees very closely 
but has the feathers of the upper surface narrowly bordered ter¬ 
minally with rusty, and the lower tail-coverts with white. Tail deep 
black, narrowly tipped with white, and crossed by two zones of gray, 
which change to w'hite or cream-color on the inner w T ebs. The speci¬ 
men in the New York Museum is marked “ 9 juv. Brazil”, and, judging 
from the rusty borders to the feathers, is undoubtedly an immature 
bird. The other specimen is marked simply “ South America ”. 
* This specimen is No. 1411 on p. 53 of “ Catalogue of the Falconidse iu the museum 
of the Society ” (Proceedings, May 21, 1873). 
