BIRDS OF NORTH AND MIDDLE AMERICA 707 



Falco richardsonii (not of Ridgway, 1870) Rhoads, Proc. Acad. Nat. Sci. Phila- 

 delphia, 1893, 40 (Okanagan, Brit. Columbia). — Lantz, Trans. Kansas 

 Acad. Sci. for 189G-1897 (1899), 219 (Lower California).— Woodcock, 

 Oregon Agr. Exp. Stat. Bull. 68, 1902, 35 (Oregon range).— Kermode, Bull. 

 Provincial Mus., 1909, 45 (near Victoria, Vancouver Island; Chilliwak, and 

 Okanagan, Brit. Columbia). 



Falco columbarius richardsoni Henshaw, Rep. Orn. Spec. Wheeler's Surv., 1876, 

 262 (Walker Basin, Calif.).— Bendire, Proc. Boston Soc. Nat. Hist., 1877, 134 

 (Camp Harney, Oreg.; nesting). — Bishop, North Amer. Fauna, No. 19, 1900, 

 75 (Circle, Alaska, Aug. 18, crit.). — Phillips, Auk, xxxviii, 1911, 73 (Mata- 

 moros, Tamaulipas, Mexico; Jan.). — Willett, Pacific Coast Avif., No. 7, 

 1912, 49 (San Fernando Valley, Calif; Oct. 31, 1903; Witch Creek, San Diego 

 County, Calif., Feb. 9, 1904).— Grinnell, Pacific Coast Avif., No. 11, 1915, 

 68 (rare winter vis. in California; Walker Basin, San Fernando Valley, and 

 Witch Creek).— Brooks, Auk, xxxiv, 1917, 39 (Chilliwak, Brit. Columbia).— 

 Dawson, Birds California (stud, ed.), iii, 1923, 1634 (genl.; California). 



Falco columbarius richardsonii Brewster, Bull. Mus. Comp. Zool., xli, 1902, 90 

 (San Jos6 del Cabo, Lower California, Oct. 31; crit.). — Wayne, Auk, xx, 1903, 

 67 (Mount Pleasant, S. C, Oct. 15, 1895) ; Birds South Carolina, 1910, 78 

 (Mt. Pleasant). 



Hypotriorchis columbarius Gray, Gen. Birds, i, 1844, 20, part; Hand-list, i, 1869, 

 21, No. 193, part. — Bonaparte, Consp. Gen. Av., i, 1850, 26, part. — Cassin, 

 Illustr. Birds California, Texas, etc., 1854, 90; to Baird, Rep. Pacific R. R. Surv., 

 ix, 1858,9. — Heermann, Pacific R. R. Rep., ii, 1855, 31. — Brewer, North Amer. 

 Ool., i, 1857, 12, part (Pacific coast). — Newbury, Pacific R. R. Rep., vi. 1857, 

 74. — WooDHOUSE, in Sitgreaves Exp., 1858, 60. — Baird, Cat. North Amer. 

 Birds, 1859, No. 7, part. — Dall and Bannister, Trans. Chicago Acad. Sci., i, 

 1869, 270 (Nulato, Alaska; whole year; Kodiak Island). — Ridgway, Proc. 

 Acad. Nat. Sci. Philadelphia, 1870, 146, part (diagn.).— Stevenson, U. S. 

 Geo). Surv. Terr., 1871, 462, part (Colorado; Wyoming). — Merriam, in 

 Hayden, U. S. Geo!. Surv. Montana, Idaho, Wyoming, Utah, 1873, 714 

 (Utah). — ScLATER and Salvin, Nom. Av. Neotr., 1873, 121, part. — Hen- 

 shaw, Ann. Lye. Nat. Hist. New York, xi, 1874, 9 (Utah). 



Aesalon columbarius Henshaw, Rep. Expl. W. 100th Meridian, 1874, 48 (Utah; 

 resident). — Ridgway and Belding, Proc. U. S. Nat. Mus., i, 1879, 434 

 (Stockton, Calif.; Oct., Nov.).— Ridgway, Proc. U. S. Nat. Mus., iii, 1880, 

 192; Nom. North Amer. Birds, 1881, No. 417, part. — Gurney, List Diurn. 

 Birds Prey, 1884, 104, part; Cat. Birds Prey, 1894, 29, part.— McLenegan, 

 Cruise Corwin, 1884, 118 (Kowak River, nw. Alaska). 



Aesalon lithofalco columbarius Goode, U. S. Nat. Mus. Bull. 20, 1883, 305, part. 



Falco sparverius Bretherton, in Friedmann, Bull. Chicago Acad. Sci., v, No. 

 3, 1935, 31, in text (Kodiak Island, "tolerably common"). 



FALCO COLUMBARIUS RICHARDSO^f^ Ridgway 



Richardson's Pigeon Hawk 



Adult male. — Similar to that of Falco columbarius columbariu^s, but 

 very much paler above and below; top of head dark gull gray to 

 neutral gray, occasionally washed with a little pale tawny, the scap- 

 ulars, interscapulars, upper wing coverts, secondaries, upper and lower 

 back, rump, and upper tail coverts paler, light neutral gray to pale 

 neutral gray, the feathers with conspicuous, narrow black shaft 



839094—50 46 



