146 BULLETIN 5 0, UNITED STATES NATIONAL MUSEUM 



ff. Breast stripes paler grayish fuscous to clove brown. 



A. gentilis gentilis, immature (extralimital) 

 ee. Mantle paler, between hair brown and fuscous. 



/. Larger (wing of adult cf 312-354; 9 321-368 mm.)8o 



A. gentilis atricapillus, immature (p. 151) 

 ff. Smaller (wing of adult cT 280-300; ? 323-339 mm.)so 



A, gentilis fujiyamae, immature (extralimital) 

 aa. Inner toe (without claw) equal to, or only slightly longer than the proximal 

 joint of the middle toe; never equal to the two proximal joints of the middle 

 toe; wing less than 300 mm. 

 h. Black bands on tail decidedly narrower than the paler interspaces, 

 c. Tail square, or scarcely rounded, 

 d. Upperparts russet. 



e. Larger, wing over IGO mm. (Colombia and Venezuela). 



A, collaris, immature (extralimital) ^^ 

 ee. Smaller, wing under ICO mm. 

 /. (Venezuela to Brazil) ._ A, superciliosus superciliosus, immature 



(extralimital) ^^ 

 //, (Nicaragua to Colombia) . 



A, superciliosus fontanieri, immature (p. 182) 

 dd. Upperparts brown or gray. 



e, Underparts more or less regularly barred. 

 /, Cheeks more or less rufescent. 



g. Banding on upper surface of tail not sharply defined. 



h. Abdomen mainly white; smaller (wing cf 141-153; 9 180-186 



mm.) (Hispaniola) A, striatus, adult (p. 198) 



hh. Abdomen with at least some dark bars; larger (wing, cT 190- 

 208; 9 230-242 mm.) (Europe east to Russia, south to the 

 Mediterranean) A. nisus, adult (extralimital) ^s 



80 These measurements are of adults, given merely to show relative size differ- 

 ences. Very young birds of either race probably run smaller. 



81 Micronisus collaris Kaup, MS. in Brit. Mus.; Sclater, Ibis, 1860, 148. — 

 Accipiter collaris Sclater, Ibis, 1860, 148, pi. 6; Gray, Hand-list, i, 33; Sharpe, 

 Cat. Birds Brit, Mus., i, 1874, 144; Swann, Synopt. List Accip., 1919, 33; Peters, 

 Check-list Birds of World, 1, 1931, 219. — Asiur collaris Swann, Synop. Accip., 

 pt. 1, 1921, 45; Monogr. Birds Prey, i, pt. 4, 1925, 250. 



82 Falco superciliosus Linnaeus, Syst. Nat., ed. 12, i, 1766, 128 (Surinam). — 

 Accipiter iinus Sharpe, Cat. Birds Brit. Mus., i, 1874, 139; Hand-list, i, 1899, 

 252. — Accipiter siiperciliosus Brabourne and Chubb, Birds South Amer., i, 1912, 

 65; Swann, Syn. Accip., pt. 1, 1921, 53; Monogr. Birds Prey, i, pt. v, 1926, 295.— 

 Accipiter superciliosus superciliosus Peters, Check-list Birds of World, i, 1931, 218. 



8» A. nisus and A. striatus are very similar and some time may be considered one 

 species, Falco nisus Linnaeus, Syst. Nat., ed. 10, i, 1758, 92; ed. 12, i, 1766, 130; 

 Kleinschmidt, Berajah, 1923. — Sparvius nisus Vieillot, Nouv, Diet. Hist. Nat., x, 

 1817, Sld.—Astur nis2is Dubois, Ois. Belg., 1854, pis, 15, 16; Schlegel, Vog, 

 Nederl., 1854, pis. 13, 14. — Accipiter nisus Pallas, Zoogr, Rosso- Asiat, i, 1827, 370; 

 Sharpe, Cat. Birds Brit, Mus., i, 1874, 132; Hand-list, i, 1899, 2^2.— Accipiter 

 nisus nisus Hartert, Vog. pal. Fauna, ii, 1914, 1151; Swann, Synop. Accip., pt. 1, 

 1921, 50; Monogr. Birds Prey, i, pt. iii, 1925, 273; Witherby, et al.. Practical Handb 

 Brit, Birds, ii, 1921, 162; Peters, Check-list Birds of World, i, 1931, 219, 



