428 



BIRDS OF THE REPUBLIC OF PANAMA PART 4 



Blake (op. cit.) noted that the birds Monniche collected between 

 May 10 and June 18 had enlarged gonads. A male I took at Santa 

 Clara, Chiriqui, on February 24, 1955, was near breeding. Skutch 

 (Pac. Coast Avif., no. 31, 1954, pp. 235-240) has studied the nesting- 

 cycle of the Bay-headed Tanager in Costa Rica, where it breeds from 

 February to September or October. The nest is placed in dense foliage 

 in trees or vines from 3 to 8 m above the ground; it is a bulky open cup 

 of moss and rootlets, within is an interior layer of leaves and grasses, 

 and a lining of grass fragments or fungal filaments. The female does 

 most of the construction. Two eggs form a full clutch; they are "white 

 or dull white with a wreath of brown or chocolate spots around the large 

 end and a sprinkling of fine dots of the same color over the remaining 

 surface. One set has shell marks of pale lilac intermixed with the 

 brown." Four eggs had average measurements of 20.2 X 13.8 mm. In- 

 cubation is performed by the female alone and takes 13 or 14 days. Both 

 parents feed the young, which fledge at 15 or 16 days of age. Some 

 pairs raise two and possibly three broods a year. Monniche (Blake op. 

 cit.) collected a bird with gonads slightly enlarged on November 22. 



TANGARA GYROLA DELECTICIA (Bangs J 



Calospxza gyroloides delecticia Bangs, 1908, Proc. Biol. Soc. Washington, 21, p. 

 160. (San Antonio, western Andes of Colombia, altitude 1600 feet.) 



Characters. — Lesser wing coverts varying from partly green to light 

 yellow. 



A male collected at Cerro Mali, Darien on February 22, 1964, had 

 the iris dark mouse brown; maxilla and tip of mandible dull black; base 

 of mandible dull brownish neutral gray, browner on lower margin of 

 rami; tarsus, toes, and claws neutral gray; posterior margin of tarsus 

 dull brownish white. 



Measurements. — Males (10 from eastern Panama), wing 72.8-80.0 

 (77.0), tail 46.0-51.2 (47.9), culmen from base 12.1-14.5 (12.9), tar- 

 sus 14.9-18.1 (16.3) mm. 



Females ( 10 from eastern Panama), wing 71.5-76.2 (73.9), tail 45.0- 

 48.7 (46.1), culmen from base 12.3-13.7 ( 13.0) , tarsus 14.4-17.7 (16.4) 

 mm. 



Resident. Uncommon in the Canal Zone and vicinity, more com- 

 mon in eastern Province of Panama and in Darien. As discussed 

 above, the population of the Canal Zone and Cerro Azul area is inter- 

 mediate between this race and bangsi. Beyond Cerro Azul, it has been 



