4?6 



BIRDS OF THE REPUBLIC OF PANAMA PART 4 



ders, usually foraging high in trees, but coming lower in clearings. It 

 is often part of large mixed flocks of other tanagers, caciques, and 

 honeycreepers. The stomach of 1 collected by E. A. Goldman at Cana, 

 Darien, held legs of an otiorhynchid 5%, other coleoptera of two species 

 80%, an ant 5%, 4 seeds of Oleaceae 10%. Leek (Living Bird, 1971, 

 p. 92) observed this species feeding on berries of a mistletoe (Oryct- 

 anthus sp.) in a tree on Barro Colorado Island, Canal Zone, and found 

 that out of 98 visits the birds spent 42% of their time in the top zone of 

 the tree, 37% in the middle, and 21% in the bottom. Ridgely (in litt.) 

 once counted a group of 14 as they departed a fruiting melastomaceous 

 tree on the Pipeline Road, Canal Zone. Slud (Bull. Amer. Mus. Nat. 

 Hist., vol. 128, 1964, p. 363) has heard these birds give squeaky, rapid, 

 chattering and tsip notes. 



The genus Heterospingus differs from Tachyphonus in having the 

 space around the nostrils densely feathered. 



HETEROSPINGUS XANTHOPYGIUS RUBRIFRONS (Lawrence) 



Tachyphonus rubrifrons Lawrence, 1865, Proc. Acad. Nat. Sci. Philadelphia, 

 p. 106. (Line of Panama Railroad, near Lion Hill Station.) 



Characters. — Smaller than nominate xanthopygius; both sexes have 

 plumage of female xanthopygius, but with yellow more extensive on 

 undertail coverts. 



A female collected at the head of the Rio Guabal, Code, on February 

 28, 1962, had the iris dull reddish brown; bill black; tarsus and toes 

 dark neutral gray. 



Measurements. — Males (7 from Panama and Costa Rica), wing 

 78.0-83.2 (81.1), tail 57.4-64.4 (60.5), culmen from base 17.6-19.8 

 (19.0), tarsus 19.2-20.7 (19.9) mm. 



Females (5 from Panama), wing 76.5-80.0 (78.1), tail 54.0-55.8 

 (54.9), culmen from base 18.2-19.3 (18.7, average of 4), tarsus 19.3- 

 20.7 (19.9) mm. 



Resident. Uncommon and local in lowlands and lower foothills of 

 the Caribbean slope from western Bocas del Toro to eastern San Bias, 

 and on the Pacific slope at the headquarters of the Rio Pacora and else- 

 where in the Cerro Azul/Jefe area, Province of Panama. Found also 

 in eastern Costa Rica. 



This race has been recorded in Bocas del Toro near Almirante, at 

 the Changuinola Dam site, and on the Rio Occidente, in Code at the 

 head of the Rio Guabal, in the Canal Zone area at Lion Hill, where 



