Carriker : List of the Birds of Costa Rica. 443 



cities of the tropics, the inhabitants would speedily be wiped out by 

 various plagues, were it not for these useful birds. In nearly all 

 places they are protected by law. 



123. Cathartes aura aura (Linnaeus). 



Vultur atcra LiNN/EUS, Syst. Nat., ed. 10, I, 1758, 86. 



Cathartes aura FRANTZIUS, Jour, fur Orn., 1869, 370 (generally distributed). — 

 Nutting, Proc. U. S. Nat. Mus., V, 1882, 405 (La Palma de Mcoya). — 

 Zei.edon, An. Mus. Nac. de C. R., I, 1887, 127. — Cherrie, Expl. Zool. 

 en C. R., 1890-1, 1893 (Terraba Valley) ; Auk, IX, 1892, 328 (San Jose — 

 not common). — Underwood, Ibis, 1896,447 (Miravalles). — Salvin and 

 Godman, Biol. Centr.-Am., Aves, III, 1901, 134 (San Jose [Underwood]). 



(Enops atcra Sharpe, Cat. Birds Brit. Mus., I, 1874, 25. — Boucard, P. Z. S. , 

 1S78, 45 (San Jose). 



Although widely distributed over the whole of the country, it is 

 nowhere abundant, and is always seen singly or in pairs. They are 

 equally common in the country and about the towns, but are more 

 timid than the preceding species. 



Family FALCONID^. 



Key to the Costa Rican Species. 



a. Underparts (not always including tail -coverts and thighs) uniformly colored: white, 

 buffy-ochraceous, ashy-blue, black, sooty-brown, or plumbeous, without 

 bars or streaks (rarely a few shaft-lines on chest or lower throat). 

 b. Under parts pure white, black, blackish-brown, or plumbeous. 



c. Under parts black or blackish-brown or plumbeous ; upper parts same 

 color. 

 d. Upper tail-coverts white apically for at least one inch, or else thighs 

 bright rufous. 

 e. Tail-coverts white, tarsus 115 mm. ; thighs and under tail-coverts 

 black. 

 f. Tail with a broad white bar across the middle, white tip, 

 and with the basal portion white, mottled with black. 



Urubitinga urubitinga, adult $ and Q • 



ff. Tail with the basal portion black, crossed by a second 



narrow white bar ; otherwise the same as the preceding. 



Urubitinga urubitinga ridgwayi, adult $ and 9 • 



ee. Thighs bright rufous, under tail- coverts white ; sides of face 



black, streaked with white. 



Parabuteo unicinctus harrisi, adult $ and Q • 

 dd. Upper tail-coverts entirely black, or only narrowly tipped with 

 white ; thighs uniform with abdomen. 

 e. Tail with numerous bars of blackish and white or grayish- white. 



