164 
White at the base of the tail more extended and broken, next the dusky 
portion, with a confused mottling or spotting of grayish and dusky. 
There is considerable variation in the plumage of this bird at all ages; 
but the variations are chiefly in details of coloration, the general style 
characteristic of the stage being preserved in all cases. In the adult 
plumage, the chief variation is in the proportionate amount of ru¬ 
fous on the rump, some specimens having the rump as uniformly 
rufous as the tibiie or lesser wing-coverts, while in others there is only 
a strong tinge or spotting of this color; the usual condition is to have 
the two colors mixed in about equal amount. The only conspicuous 
variation noticeable in the series under examination is in the markings 
of the tail-feathers, a single specimen, No. 9131, having the white of the 
tip extending on some feathers along the edge and thus connected with 
the basal white. This condition is so entirely exceptional, however, 
that we are led to believe that it is purely individual, and outside the 
normal variations which the species ordinarily presents. In the perfect 
adult plumage of this form, there are no white or ochraceous streaks on 
the throat or cheeks, nor any white other than that described above, ex¬ 
cept a faint white sprinkling, seen in some individuals, on the inner 
webs of the primaries. 
We still separate the northern birds of this species from the southern 
ones, notwithstanding Mr. Sharpe and other prominent authorities unite 
them, for the reason that we have yet to see a single South American 
specimen in which the dusky and rufous of the plumage assumes that 
uniformity characteristic of the adult specimens from Mexico and ad¬ 
joining provinces. The Chilian specimen described above is the black¬ 
est example we have seen of the former, while Temminck’s plate, cited 
above (PI. Col. 313), represents about the average style. The adult plum¬ 
age of the South American bird seems, therefore, to correspond with the 
immature stage of the northern form, or that stage in which the tail is 
uniform black on the upper surface, with the characteristic basal and 
terminal white bauds, the black, especially that of the lower surface, much 
broken by whitish edgings and spottings,and the tibiee merely barred with 
ferruginous. It is barely possible that we have not seen the most per¬ 
fect plumage which the adult of the South American bird attains, but 
Mr. J. II. Gurney, than whom there is not a more competent authority, 
in commenting on our statement to this effect in History of North Ameri¬ 
can Birds (vol. iii, p. 249), says that so far as he has had an oppor¬ 
tunity of examining specimens, our observation is correct. (Cf. Ibis, 
April, 1875, p. 235.) 
List of specimens in United States National Museum. 
a. UNICINCTUS. 
Catalogue 
No. 
Sex and 
age. 
Locality. 
Date. 
13907 
13908 
16572 
32971 
32972 
36667 
*18813 
*18814 
48815 
49507 
54111 
54935 
9 ad. 
cT ad. 
— juv. 
n 
Chili . 
Chili . 
+ 
(j JUV. 
— juv. 
_(io. 
June, 1864 
_do. 
n 
flo . 
+ 
9 .iuv. 
0 jnv. 
cf !i>iv. 
— ad. 
_do. 
Concliitas, Buenos Ayres. 
(riiayfl.qnil Rp.nndor . 
July, 1864 
May, 1867 
do . 
Donor. 
Lieutenant Gillies. 
Do. 
W. Evans. 
Verreaux. 
Do. 
X. li. Mils. Rio. 
Nat. Mus. Cliili. 
Do. 
Do. 
W. II. Hudson. 
J. F. Reeves. 
Dr. Dostruge. 
Other specimens examined .—In mus. Pliilad. Acad., 9; Am. Mus., N. Y., 1; Boston Sec. 
4; total, 26. 
