FAMILY ACCIPITRIDAE 235 



BUTEOGALLUS ANTHRACINUS ANTHRACINUS (Deppe) 



Falco anthraciniis W. Deppe, Preis — Verz. Saugeth. Vog. Amphibien, Fische u. 



Krebse, Deppe u. Schiede Mexico gesammelt., 1830, p. 3. (Veracruz.) 

 Urubitinga anthracina cancrivora A. H. Clark, Proc. Biol. Soc. Washington, 



vol. 18, Feb. 21, 1905, p. 63. (Barrouallie, St. Vincent.) 



Characters. — Larger, shown mainly in length of wing. 



Measurements (from the entire geographic range). — Males (33 

 specimens) wing 354-378 {Z6Z), tail 173-216 (200), culmen from 

 cere 23.5-28.8 (26.2, average of 32), tarsus 84.0-93.8 (88.4) mm. 



Females (36 specimens), wing 365-398 (377), tail 190-226 (208), 

 culmen from cere 25.2-30.5 (27.7), tarsus 83.5-94.0 (89.3) mm. 



An adult male from Mandinga, taken on January 29, 1957, had 

 the iris wood brown ; cere orange ; base of mandible and bare area 

 below nostril to gape light orange; rest of bill neutral gray; loral 

 area, and bare skin above eye, chrome yellow ; lower eyelid dull 

 whitish ; tarsi and toes chrome yellow ; claws black. 



Resident. Fairly common in the tropical lowlands, mainly near the 

 coast, from Bocas del Toro to eastern San Bias ; in Darien along the 

 Chucunaque and Tuira Rivers, above the influence of tide, and in 

 hill country near the coast ; Isla Coiba. 



Three females from Isla Coiba, with the wing 364, 369, and 370 

 mm. respectively, belong evidently with this form, an isolated colony 

 on this large, remote island. 



Birds from the Caribbean slope from western Colon to western 

 San Bias are somewhat smaller but come within the lower limit of 

 size given above. Birds in immature plumage throughout the range 

 often are smaller than adults, a fact that should be kept in mind in 

 identification, as some may approach or equal the size found in adults 

 of the smaller race. At Jaque, in eastern Darien, the race hangsi, in 

 typical small form is common in the mangrove swamps at the mouth 

 of the Rio Jaque, but an adult female that I shot on a high roclcy 

 headland above a sand beach along the coast toward Colombia is 

 certainly the larger race. 



The eggs are described by Bent (U. S. Nat. Mus. Bull. 167, 1937, 

 p. 26) as dull white, spotted sparingly with various shades of brown, 

 with the shell finely granulated. Some have the markings much 

 reduced so that they appear almost plain white. The range of measure- 

 ments is 50-66.5x42.3-48.3 mm. In the northern limit of the range, 

 from southern Arizona to southern Texas, the birds may have from 

 one to three eggs in the nest, but in tropical areas a single tgg is usual, 

 increased rarely to two. 



