BIRDS OF NORTH AND MIDDLE AMERICA 521 



LEIGH, Occ. Pap. Mus. Zool., Louisiana State Univ., No. 3, 1939, 27 (ne. 



Mexico; Tamaulipas: Guemes and G6mez Farias). — Wetmore, Proc. U. S. 



Nat. Mus., Ixxxvii, 1939, 186, in text. — Sutton and Pettingill, Auk, lix, 



1942, 10 (G6niez Farias region, sw. Tamaulipas; spec). 

 Geranospiza caerulescens var. niger Ridgway, Proc. Boston Soc. Nat. Hist., xvi, 



1873, 84 (diagnosis). — Hellmayr, Nov. Zool., xxiii, 1921, 178 (range). 

 Gernospiza caerulescens b. var. niger Ridgway, Proc. Boston Soc. Nat. Hist., xvi, 



1873, 85 (syn.). 



Geranospizias caerulescens nigra Zeled6n, Cat. Aves Costa Rica, 1882, 27; Proc. 

 U. S. Nat. Mus., viii, 1885, 112 (Costa Rica). — Lantz, Trans. Kansas 

 Acad. Sci. for 1896-97 (1899), 219 (Rinconada, Sinaloa). 



Geranospizia caerulescens niger Bangs and Penard, Proc. Biol. Soc. Washington, 

 xxxiv, 1921, 89, in text. 



Geranospizias caerulescens niger Swann, Synopt. List Accip., pt. 1, 1919, 17, part 

 (s. Mexico to Panama) ; Synop. Accip., pt. 1, 1921, 28, part; pt. 4, 1922 (errata 

 and add.). — Sturgis, Field Book Birds Panama Canal Zone, 1928, 131 

 (descr. ; habits; Panama). — Griscom, Bull. Amer. Mus. Nat. Hist., Ixiv, 1932, 

 151 (distr. in Guatemala; rare). 



Geranospiza caerulescens nigra Sassi, Temminckia, iii, 1938, 298 (Costa Rica: 

 Bebedero; spec; colors of soft parts). 



Geranospiza gracilis var. niger Lawrence, Mem. Boston Soc. Nat. Hist., ii, 



1874, 299 (Mazatldn, Sinaloa; habits). 



Ischnoscelis aterrimus Lichtenstein, Nom. Mus. Berol., 1854, 4 (Mexico). 

 Geranospiza gracilis (not Falco gracilis Temminck, 1824) Sclater, Proc. Zool. Soc 



London, 1856, 285 (C6rdoba, Veracruz).— Gray, Hand-list, i, 1869, 31, No. 



289, part. — Cubas, Cuadro Geogr., Estadistico, Descr. e Hist, de los Estados 



Unidos Mexicanos, 1884, 173 (common names, Mexico). 

 Geranospiza coerulescens (not Sparvius caerulescens Vieillot, 1817) Sclater and 



Salvin, Ibis, 1859, 218, part (s. Mexico). — Lawrence, Ann. Lye Nat. 



Hist. New York, vii, 1861, 289, part (Panama). 

 Geranospiza caerulescens Salvin and Sclater, Ibis, 1860, 44 (Duenas, Guate- 

 mala; food; fresh colors of unfeathered parts). 

 Geranospizias caerulescens Stone, Proc. Acad. Nat. Sci. Philadelphia, 1890, 204 



(Shkolak, Yucatdn). 

 Nisus hemidactylus (not Falco hemidactylus Temminck) Schlegel, Mus. Pays- 



Bas, ii, No. 4, livr. 1, 1862, 53, part (monogr.). 



GERANOSPIZA NIGRA BALZARENSIS Sclater 



Ecuadorian Frog Hawk 



Adult (sexes alike). — Similar to the adult of Geranospiza nigra 

 nigra, but generally paler, neutral gray to deep neutral gray, the nar- 

 row white bars on the abdomen, flanks, and thighs fewer, fainter, and 

 sometimes obsolete; the under tail coverts mostly like the abdomen, 

 but with a few that are pinkish buff crossed by two or three very 

 broad bands of blackish; the more proximal of the two tail bands 

 washed with pinkish buff. 



Immature (sexes alil^e). — Similar to the adult, but with all or 

 almost all the under tail coverts pinkish buff crossed by two or three 

 very broad blackish bands. 



