107 
rufous on tlie tibiae; crissum immaculate, but all other parts marked 
with brown, the bi east, side, and abdomen having lanceolate streaks of 
clear dark brown, and the tibiae having large transverse spots of lighter 
brown, mixed with rufous ; throat with a medial series of narrow dusky 
streaks. Wing, 8.30; tail, 8.00; culmen, 0.52; tarsus, 2.45; middle 
toe, 1.40. 
Adult female (No. 32,074, Nat. Mus.):—Exactly like the male. Wing, 
9.85; tail 8.80; culmen, 0.60 ; tarsus, 2.80; middle toe, 1.70. 
The sexes differ in measurements as follows :— 
Males; Wing, 8.25-8.30; tail, 7.65-8.00; culmen, 0.50-0.53; tarsus, 
2.25-2.45 ; middle toe, 1.40. 
Females: Wing, 8.60-9.85; tail, ?.50-8.80; culmen, 0.60-0.62; tarsus, 
2.65-2.S0 ; middle toe, 1.70. 
List of specimens in United States National Museum. 
Catalogue No. 
Original No. 
Sex and age. 
Locality. 
When col¬ 
lected. 
' 
From whom received. 
32977 
o 
Chile. 
Verreaux.... 
32978 
<3 
.... do. 
.. do. 
48827 
16 
d 
Chile, Valdivia. 
* 
J une —, 18G4 
Nat. Mus. Chile. 
NISUS BICOLOR. 
Spanius bicolor Vieill. N. D. s. 1817, 325; Enc. Moth, iii, 1823, 1265.— Pucher. R. 
Z. 1850, 92. 
Cooperastur bicolor Bonap. Rev. et Mag. Z^ol. 1854, 538. 
Accipiter bicolor Strickl. Orn. Syn. i, 1855, 110.— Scl. & Saev. P. Z. S. 1869, 252 
(Maruria, Venezuela); Ex. Orn. ix, 1869, 137, pi. lxix; ib. xi, 170; P. Z. S. 
1870, 838 (coast of Honduras); P. Z. S. 1870, 787 (Venezuela); Nom. Neotr. 
1873,120. — Gray, Hand List, i, 1869, 33.— Salvin, P. Z. S. 1870, p. —(Veragua). 
—Sharpe, Cat. Ace. B. M. 1874, 154. 
Nisus bicolor Giebel, Thes. Orn. 1872, 263. 
Nisus pileatus var. bicolor Ridgw. Pr. Boston Soc. N. IT. May, 1873, 89. 
Nisus variatus Less. Tr. 1831, 61.— Pucher. R. Z. 1850, 6, 210. 
Accipiter sexfasciatus Swains. An. Menag. 1837, 282. 
Nisus sexfasciatus Caban. Schomb. Reis. Guian. iii, 1848, 736. 
Astur sexfasciatus Light. Nomencl. Av. 1854, 4. 
Micrastur dynastes Verreaux, in Bonap. Notes Orn. 1854, 4.' 
lihijnehomegus dynastes Bonap. Notes Orn. 1854, 4. 
Accipiter erythrocnemis Scl. P. Z. S. 1860, 96 (not of Gray, 1848). 
Accipiter pileatus Salvin, Ibis, 1861, 354 (S. Mexico and Guatemala); ib. 1869, p. — 
(Costa Rica).— Lawrence, Ann. N. Y. Lyc. 1868, 134 (Costa Rica). 
Hal). —Central District of Tropical America, from Southern Mexico to 
Ecuador and Guiana. Nicaragua, Costa Rica, and Surinam (Phila. 
Acad.); Costa Rica, Yeragua, and Panama (Nat. Mus.); Cayenne 
(Boston Soc.). 
Wing, 8.00-10.00; tail, 7.20-8.80; culmen, 0.55-0.75; tarsus, 2.25-2.70; 
middle toe, 1.45-1.80. Fourth and fifth quills longest; first shortest; 
outer five with inner webs emarginated. Tail slightly rounded. 
Adult: —Pileum, plumbeous-black. Tibise bright cinnamon-rufous; 
lining of the wing white, usually mixed with grayish, or with darker 
shaft-streaks, and sometimes tinged with rufous along the outer border of 
the wing. Crissum white, sometimes tinged with grayish or rufous. 
Tail black, crossed by three to four narrow bands of dull plumbeous or 
slate, these indistinct on the upper surface, whitish underneath. Inner 
