348 BIRDS OF THE REPUBLIC OF PANAMA PART 2 



white ; claws black. Another female from Cerro Campana, Panama, 

 March 3, 1951, had the maxilla black ; tip of mandible brownish black ; 

 base dull reddish brown. A third from Armila, San Bias, February 

 22, 1963, had the base of the mandible pale dull wine-red, and the 

 tarsus and toes dull pink. 



Measurements. — Males (10 from Colon, Panama, San Bias, and 

 Darien), wing 67.0-69.8 (68.4), tail 40.4-42.8 (41.3), culmen from 

 base 23.6-26.9 (25.0) mm. 



Females (10 from Code, Panama, San Bias, and Darien), wing 

 62.0-64.8 (63.1), tail 36.4-39.8 (37.5), culmen from base 24.7-27.2 

 (25.9) mm. 



Resident. Locally common in forest areas on the Caribbean slope 

 from western Bocas del Toro, northern Veraguas, and northern Colon 

 to eastern San Bias ; recorded at 900 meters on Cerro Campana, 

 western Province of Panama, and at 575 meters on the upper Rio 

 Tacarcuna, Darien. 



It is interesting that this race ranges to the Pacific slope on the 

 crest of the mountain ridge at Cerro Campana, where Chalybura 

 buffonii micans is found at the base. It crosses also to the Pacific side 

 on the lower slopes of Cerro Tacarcuna, and is found across the 

 higher levels which mark the divide on Cerro Azul. Elsewhere it is 

 known only from the Caribbean side of the Isthmus. 



The numerous specimens now available from the middle Chagres 

 Valley (Candelaria Hydrographic Station), eastern San Bias (Armila, 

 Puerto Obaldia), and the lower slopes of Cerro Tacarcuna, Darien. 

 which all agree with isaurae of farther west, cover the range assigned 

 to the supposed race incognita, described by Griscom, so that this is 

 not recognized. 



The distinct form melanorrhoa Salvin, of the Caribbean lowlands 

 of Nicaragua and Costa Rica, may be found along the Rio Sixaola on 

 the western boundary of the Republic, as Carriker (Ann. Carnegie 

 Mus., vol. 6, 1910, p. 536) records it as abundant on the Costa Rican 

 side of that stream. Compared to isaurae the male has the under tail 

 coverts black, and the foreneck and upper breast green. Females of 

 the two forms are less distinctive, that of melanorrhoa being glossed 

 with green on the sides (less extensively on the breast), with the under 

 tail coverts and femoral tufts gray. The two intergrade in western 

 Bocas del Toro, males of isaurae from this area often having the under 

 tail coverts basally black. Eisenmann and Howell, in a detailed 

 survey of these birds (Condor, 1962, pp. 300-310), show clearly that 

 melanorrhoa, formerly considered specifically distinct, intergrades 



