490 



BIRDS OF THE REPUBLIC OF PANAMA PART 4 



Measurements. — Males (7 from eastern Province of Panama and 

 Darien), wing 65.5-70.0 (67.5), tail 44.6-48.1 (46.8), oilmen from 

 base 12.3-14.1 (13.6), tarsus 14.7-17.2 (16.4) mm. 



Females (9 from eastern Province of Panama and Darien), wing 

 56.0-60.6 (57.8), tail 35.8-42.9 (39.8, average of 8), oilmen from base 

 12.9-14.3 (13.6), tarsus 14.7-16.1 (15.7) mm. 



Resident. Known from a few localities, in eastern Province of 

 Panama from the Cerro Azul/Cerro Jefe area and the El Llano-Carti 

 road (Eisenmann and J. Pujals) , and in Darien from Cerro Tacarcuna, 

 Cana, Cerro Sapo, Cerro Pirre, and Cerro Quia. On Tacarcuna, it has 

 been collected between 630 and 720 m, and on Cerro Azul and Cerro 

 Sapo at 900 m. Ridgely has seen it on Cerro Azul up to 1000 m. Bond 

 and de Schauensee (Acad. Nat. Sci. Philadelphia Mon. no. 6, 1944, 

 p. 44) record that males taken in April at Cerro Sapo had enlarged 

 testes, and a female was noted as "laying." 



CHLOROSPINGUS OPHTHALMICUS (DuBus): Common Bush- 

 tanager, Frutero Rastrojero Comiin 



Arremon ophthalmicus DuBus, 1847, Bull. Acad. Roy. Sci., Lettr. et Beaux-Arts 

 de Belgique, 14, (pt. 2), p. 106. (Jalapa, Veracruz, Mexico.) 



Small; head dusky brown or blackish; upper surface yellowish 

 green; undersurface more yellowish with center of belly white. 



Description. — Length 128-140 mm. Adult male, top and sides of 

 head dull brown or blackish (punctulatus) ; rear half of orbital ring 

 and spot behind eye white; upper surface, including wing coverts and 

 tail, yellowish green; remiges dusky with outer webs edged color of up- 

 per surface; throat white, flecked dull brown, or yellow flecked black- 

 ish (punctulatus) ; band across breast dull yellow tinged green; sides, 

 flanks, and undertail coverts yellowish green; rest of undersurface 

 white; bend of wing light yellow; underwing coverts white. 



Female like male, but crown slightly duller, sometimes tinged green. 



The Common Bush-tanager inhabits forest, forest borders, and 

 shrubby clearings. Races occur from central Mexico to northwestern 

 Argentina. I have usually found the bush-tanager moving actively, like 

 a warbler, through the lower growth, although it is sometimes seen in 

 the tree crown. Except when nesting, it travels in small groups that are 

 often the nucleus for many other species that join mixed flocks. Bus- 

 kirk et al. (Auk, 1972, pp. 612-624) have examined in detail the daily 

 activities of several flocks at Cerro Punta; they found bush-tanagers 

 to be most active in the morning and later afternoon. At night they 

 usually roost in loose groups. When bush-tanagers are active and call- 



