BIRDS OF NORTH AND MIDDLE AMERICA 611 



times barred with the same, the feathers with darker shaft streaks; 

 lower tail coverts very indistinctly marked in much the same manner; 

 auriculars, cheeks, and throat plain dirty white, as in the adult; iris 

 dark brown; bill light bluish; tarsi and toes nearly "Naples yellow"; 

 lores "not [=nearl chrome yellow" (Bryant) .^^ 



Natal down.- — General color light Isabella color, or brownish white, 

 with an umber-brown patch over the scapula, connected with one 

 over the radius and ulna; pileum uniform umber-bro^vn. 



Adult male.—^nng 381-402 (393.3); tail 260-279 (265.7); culmen 

 from cere 32-33.5 (32.8); tarsus 84-92 (89.3); middle toe without 

 claw 45-53 (50.7 mm.) (6 specimens). 



Adult jemale.—Wmg 394-418 (407.5); tail 260-286 (272.6); culmen 

 from cere 32-33 (32.7); tarsus 83-92 (88.5) ; middle toe without claw 

 50-56 (53.5 mm.) .2* 



Range. — Restricted to Guadalupe Island off the coast of Baja 

 California; now extinct. 



Type locality. — Guadalupe Island. 



Polyborus luiosus Ridgway, Bull. U. S. Geol. and Geogr. Surv. Terr., ser. 2, No. 6, 

 1876, 455, 459, 460 (Guadalupe Island, Lower California; coll. U. S. Nat. 

 Mus.); No. 2, 1876, 192 (monogr.) ; Bull. Nuttall Orn. Club, ii, 1877, 60, 61; 

 Proc. U. S. Nat. Mus., iii, 1880, 193; Nom. North Amer. Birds, 1881, No. 

 424; Man. North Amer. Birds, 1887, 254. — Gurnet, List Diurn. Birds Prey, 

 1884, 12; Cat. Birds Prey, 1894, 18. — American Ornithologists' Union, 

 Check-list, 1886, and ed. 2, 1895, No. 363; ed. 3, 1910, 168; ed. 4, 1931, 73.— 

 Bryant, Proc. California Acad. Sci., ser. 2,!Bu11. 6, ii, 1887, 281 (Guadalupe 

 Island; habits; fresh colors of unfeathered parts; etc.). — Rothschild and 

 Hartert, Nov. Zool., ix, 1892, 404 (crit.).— Sharpe, Hand-list, i, 1899, 

 243. — Thayer and Bangs, Condor, x, 1908, 106 (now extinct!). — Swann, 

 Synopt. List Accip., pt. 1, 1919, 8; Synop. Accip., pt. 1, 1921, 13; Monogr. 

 Birds Prey, i, 1925, 73 (monogr.). — Grinnell, Univ. California Publ. Zool., 

 xxxii, 1928, 113 (distr. in Lower California, records). — Phillips, Verh. 

 6th Internat. Orn. Kongr., 1929, 506 (extinct; formerly on Guadalupe 

 Island). — Peters, Check-list Birds of World, i, 1931, 281. — Abbott, Condor, 

 XXXV, 1933, 10 (hist.; list specimens). — Wetmore, Condor, xxxv, 1933, 206, 

 in text (California: Guadalupe Island; 1 skeleton). — Bent, U. S. Nat. Mus. 

 Bull. 170, 1938, 136 (life hist.). 



Caracara lutosus Hellmayr and Conover, Cat. Birds Amer., pt. 1, No. 4, 1949, 

 287 (syn.; range). 



25 In the adult plumage all the contour feathers have distinctly black shafts, 

 especially on the lower surface and upper tail coverts; on the tibiae and anal region 

 the dark bars are smaller and more faint than elsewhere, and incline to a sagittate 

 form; the feathers of the lining of the wing are sometimes narrowly tipped with 

 light Isabella color, or tawny brown, and the transverse bars are faintest and most 

 confused on the upper portion of the rump. In both adult and immature stages 

 there is considerable variation, but all v/ithin the limits of the above diagnosis 

 (Ridgway). 



2* Ten specimens. The measurements given are partly from original measure- 

 ments and partly from literature. 

 839094 — 50 40 



