12 
ZOOLOGY. 
olive lustre. Length about 16 inches; wing 13£. The only specimen known at present was 
collected not far from Fort Fillmore hy Dr. T. C. Henry. 
BUTEO MONTANUS, Nuttall, (p. 26.)—The Western Red-tailed Hawk. 
Butco montanus, Nutt. Manual Orn. U. S. I, 112, (1840.) 
Adult female. —Throat and neck before dark brown mixed with white; the brown color more extended, and, with the abdomen, 
tibiae, and undor tail coverts, much more tinged with rufous than in B. borealis. Tibiae distinctly barred transversely with rufous. 
Size rather larger. General appearance similar to Butco borealis, but rather larger, and with the wings longer; throat and neck 
before brown; breast and abdomen white, with a very pale fulvous or rufous tinge; sides with numerous narrow lanceolate and 
oblong spots of dark brown and rufous; abdomen with a broad transverse band composed of spots of the same description. 
Tibial feathers pale rufous, with numerous transverse bands of a darker shade of the samo color. Under wing coverts pale 
yellowish white, with brown spots. Tail above bright rufous narrowly tipped with white, with a subterminal band of black, and 
a few indications of transverse stripes near the shafts of the feathers. Upper parts of the body dark umber brown, with partially 
concealed ashy white and pale fulvous spots and transverse bands, especially on the scapulars and shorter quills. Upper tail 
coverts reddish white, with transverse bands of dark brown. Bill dark bluish ; tarsi and toes yellow. 
This species can only be distinguished from B. borealis by its larger size, the greater extent of the dark color of the throat, 
and the prevalence of the rufous color of the abdomen and tibiae. In some specimens, however, the abdomen is nearly pure white. 
Another plumage of this bird, apparently adult, of both sexes, is as follows, and is the most easily recognized of any stage: 
Adult male and female —Like the preceding, but with the under parts pale rufous, lighter on the breast, some feathers, 
especially on the abdomen, having longitudinal lines and spots of dark brown. Tibiae rufous, with transverse bars of a darker 
shade of the same color. Tail bright rufous; tip paler, with a subterminal band of black. This second plumage, described 
above, we have never seen in Butco borealis. 
Sangre del Christo Pass. (6.) Iris whitish. 
CIRCUS HUDSONIUS, Linn® us, (p. 38.)—The Marsh Hawk. 
Falco liudsonius , Linn. Syst. Nat. I, 123, (1766.) 
Adult. —Form rather long and slender; tarsi long; ruff quite distinct on the neck in front. Entire upper parts, head, and 
breast, pale bluish cinereous; on the back of the head mixed with dark fulvous; upper tail coverts white. Under parts white, 
with small cordate or hastate spots of light ferruginous; quills brownish black, with their outer webs tinged with ashy, and a 
large portion of their inner webs white; tail light cinereous, nearly white on the inner webs of the feathers, and with obscure 
transverse bands of brown ; under surface silky white; under wing coverts white. 
Younger. —Entire upper parts dull umber brown, many feathers edged with dull rufous, especially on the neck; under parts 
dull reddish white, with longitudinal stripes of brown, most numerous on the throat and neck before; tibiae tinged with reddish; 
upper tail coverts white. 
Young. —Entire upper parts dark umber brown; upper tail coverts white. Under parts rufous, with longitudinal stripes of 
brown on the breast and sides ; tail reddish brown, with about three wide bands of dark fulvous, paler on the inner webs. Tarsi 
and toes yellow. 
Total length, female, 19 to 21 inches; wing 15£, tail 10 inches. Male, total length 16 to 18 inches; wing 14£, tail 8J to 9 
inches. 
6859. Rocky mountains. (4.)—Desert between White river and San Rafael creek, Utah. (28.) 
TINNUNCULUS SPARYERIUS, Yieill. (p. 13.)—Sparrow Hawk. 
Falco sparverius, Linn. Syst. Nat. I, 1766, (128.) 
No. 8519. Cochetope Pass. 
OTUS WILSONIANUS, Lesson, (p. 53.)—The Long-eared Owl. 
Otus wilsonianus, Lesson, Traite d’Orn. I, p. 110. (1831.) 
Sp. Ch.—E ar tufts long and conspicuous; eyes rather small; wings long; tarsi and toes densely feathered. Upper parts 
mottled with brownish black, fulvous, and ashy white; the former predominating. Breast pale fulvous, with longitudinal stripes 
of brownish black; abdomen white ; every feather with a wide longitudinal stripe, and with transverse stripes of brownish black; 
