374 BULLETIN 50, UNITED STATES NATIONAL MUSEUM 



Antenor harrisi Gurnet, List Diurn. Birds Prey, 1884, 71, part; Cat. Birds Prey, 

 1894, 25, part. 



Asturina harrisi Reichenow, Die V^ogel, i, 1913, 384. 



Buieo unicindus (not Falco unicinctus Temminck, 1824), Morton, Proe. Acad. 

 Nat. Sci. Philadelphia, iii, 1846, 98 (near Natchez, Miss.) — Gray, Hand-list, 

 i, 1869, 7, No. 55, part (s. United States; Mexico; Veraguas). 



Uruhitinga unicinctus Bonaparte, Consp. Gen. Av., i, 1850, 29. 



Uruhilinga unicincta Sclater and Salvin, Ibis, 1859, 216 (Guatemala); Noin. 

 Av. Neotr., 1873, 119, part (Mexico). 



Morphnus unicinctus Cassin, Proe. Acad. Nat. Sci. Philadelphia, vi, 1853, 453 

 (s. North America); vii, 1855, 284 (Texas). — Brewer, North Amer. Oology, 

 i, 1857, 60, pi. 2, figs. 20, 21.— Finsch, Verh. Naturw. Ver. Bremen, ii, 1870, 

 363 (Mazatldn, Mexico). — Cubas, Cuadro Geogr., Estadistico, Descr. 

 e Hist, de los Estados Unidos Mexicanos, 1884, 166 (common names; Mexico). 



Craxirex unicinctus Cassin, in Baird, Rep. Pacific R. R. Surv., ix, 1858, 46. — 

 Baird, Rep. U. S. and Mex. Bound. Surv., ii, pt. 2, 1859, 4 (Brownsville and 

 Oyster Point, Tex.); Cat. North Amer. Birds, 1859, No. 46. — Dresser, Ibis, 

 1865, 329 (s. Texas; colors of unfeathered parts). — Salvin, Proe. Zool. Soc. 

 London, 1867, 158 (Santa Fe, Veraguas, Panama). 



Spizigeranus unicinctus Sclater, Proe. Zool. Soc. London, 1860, 288 (Babahoyo, 

 Ecuador). 



Asturina unicincta Schlegel, Mus. Pays-Bas, Asturinae, 1862, 2, part (Mexico). 



Erythrocnema unicincta Sharpe, Cat. Birds Brit. Mus., i, 1874, 85, part (in 

 syn.; southernmost North America, part). — Salvadori and Festa, Boll. 

 Mus. Zool. Torino, xv, 1900, 30 (Ecuador). 



Parabuteo unicinctus Ihering and Ihering, Av. Brazil, 1907, 87, part (in state- 

 ment of range). — American Ornithologists' Union, Check-list North 

 Amer. Birds, ed. 3, 1910, 157, part. — Housse, Rev. Universitaria, Nos. 8-9, 

 1934, 1005, part (monogr.; plumage; habitsj. — Engels, Auk, Iviii, 1941, 63, 

 64, in text (skeletal ratios). 



Buteo alhicaudatus Clark, Auk, xix, 1902, 261 (Margarita Island, Venezuela, 

 part) . 



PARABUTEO UNICINCTUS SUPERIOR Tan Rossem 



Western Dusky Hawk 



Adult (sexes alike) . — Similar to that of Parabuteo unicinctus harrisi, 

 but larger (this difference more pronounced in females than in males) 

 and the general coloration somewhat darker — fuscous-black to almost 

 black. 



Juvenal (sexes alike). — Similar to the corresponding stage of 

 Parabuteo unicinctus harrisi, but larger, and averaging slightly darker, 

 the underparts often with the dark streaks so extensive as to make 

 for an almost uniform tone, and the thighs often almost as dark as 

 in the adults. 



Natal down. — Similar to that of Parabuteo unicinctus harrisi. 



Adult maZe.— Wing 324. 4-357. 1 (337. 8) ; tail 224-257 (245. 2) ; 

 culmen from cere 25-27. 5 (26. 2) ; tarsus 80-88 (84. 6) ; middle toe 

 without claw 44. 5-49 (46. 4 mm.).^^ 



" Four specimens from Arizona, Baja California, and Sinaloa. 



