t/\MILY FRINGILLIDAE 



571 



known as far west as La Chorrera, western Province of Panama, and 

 as far east as Buenaventura Island, near Portobelo, Colon, and the 

 Candelaria and Peluca Hydrographic Stations at the headwaters of the 

 Rio Chagres. Specimens in almost pure corvina plumage have also 

 been collected in some of the same Canal Zone localities. In addition to 

 the variability usual for this population, Olson (Wilson Bull., 1965, 

 p. 127) also reported a specimen from the Canal Zone in which part of 

 the black in the underparts was replaced by chestnut. There are 3 more 

 such specimens in the Smithsonian collections taken in the Canal Zone 

 in 1911 by E. A. Goldman. 



In the Canal Zone, the breeding season runs, in different years, from 

 May to October, but the height of the season is in July and August. 

 Gross (Auk, 1952, pp. 433-446) has studied the nesting of the popu- 

 lation of Barro Colorado Island. He found that the female builds the 

 nest unaided and the incubation period is 12 days. The young are 

 fed a mixture of insects and seeds, the latter predominating, by both 

 parents. Some pairs will lay a second clutch if the first is destroyed, 

 but it is not known if any normally raise two broods. 



SPOROPHILA NIGRICOLLIS NIGRICOLLIS (Vieillot): Yellow- 

 bellied Seedeater, Arrocero Ventriamarillo 



Pyrrhula nigricoUis Vieillot, 1823, in Bonnaterre and Vieillot, 1823, Tabl. End. 

 Meth., Ornith., 3, livr. 93, p. 1027. (Brazil.) 



Small; male, forecrown, throat, and breast black, rest of upper sur- 

 face grayish olive; rest of undersurface white, tinged pale yellow; fe- 

 male upper surface and throat olive-brown; rest of undersurface pale 

 yellow tinged brown on sides and flanks. 



Description. — Length 99-103 mm. Adult male, forecrown, sides of 

 head to eye, throat, and breast black, fading on rest of upper surface to 

 grayish olive; rest of undersurface white, tinged pale yellow; under- 

 wing coverts white. 



Female, entire upper surface olive-brown; wings and tail dusky, 

 edged olive-brown; throat and sometimes upper breast light olive- 

 brown; rest of undersurface very pale buffy yellow, sometimes more 

 brownish on sides and flanks; underwing coverts white and pale buffy 

 yellow. 



Immature male, like adult male, but only spotted with black. 



A male collected at Rio Indio, Colon, on February 20, 1952, has the 

 iris reddish brown; bill light neutral gray; tarsus and toes fuscous. A 

 male taken at Chame. Province of Panama, on June 22, 1953, had the 



