4o8 



BIRDS OF THE REPUBLIC OF PANAMA PART 4 



18 days; as in other euphonias, this is longer than most other birds of 

 this small size. Unfortunately, Skutch never found a nest in which the 

 young escaped predation for more than a day after hatching, and so has 

 no information on their care. 



EUPHONIA LANIIROSTRIS CRASSIROSTRIS Sclater: Thick-billed 

 Euphonia, Piquigordo 



Euphonia crassirostris P. L. Sclater, 1857, Proc. Zool. Soc. London, 24 (1856), 

 p. 277. (New Grenada, Bogota.) 



Very small; bill thicker than in other euphonias; male, bright yellow 

 forecrown and undersurface; sides of head and rest of upper surface 

 yellowish green; undersurface greenish yellow. 



Description. — Length 97-104 mm. Adult male, forecrown to just 

 behind eye yellow; lores, sides of head, and entire upper surface, includ- 

 ing wing coverts, glossy dark blue, slightly more purplish on head and 

 nape; remiges blackish, edged dark blue on outer webs and white on 

 basal half of inner webs; rectrices blackish, edged dark blue, with large 

 white patch on inner web of outer two pairs; entire undersurface rich 

 yellow; bend of wing yellow; inner wing coverts white. 



Adult female, sides of head and entire upper surface, including wing 

 coverts, yellowish green; remiges and rectrices dusky brownish, with 

 outer webs edged yellowish green; entire undersurface greenish yel- 

 low, except for lower belly, which is light yellow; underwing coverts 

 white. 



Immature male, like adult, but blue areas yellowish green, gradually 

 replaced with blue: 



A female collected at Puerto Armuelles, Chiriqui, on February 7, 

 1966, had the iris dark wood brown; base of maxilla below nostril, and 

 mandible except tip bluish neutral gray; rest of bill black; tarsus and 

 toes dusky neutral gray; claws fuscous. An immature male collected 

 there February 1 1 was similar, but an adult male taken there February 

 14 had the iris dark reddish brown and the tarsus and toes fuscous. 



Measurements. — Males (10 from Panama), wing 59.8-63.9 (61.6), 

 tail 32.6-38.4 (35.2), oilmen from base 9.3-10.3 (10.0), tarsus 13.2- 

 15.8 (14.4) mm. 



Females (10 from Panama), wing 57.5-62.0 (58.8), tail 32.2-35.7 

 (33.6), oilmen from base 9.2-10.8 (9.8), tarsus 13.9-15.2 (14.7) mm. 



Resident. Common in the humid lowlands and foothills along the 

 entire Pacific slope and on the Caribbean slope from El Uracillo, Code, 

 eastward. In western Chiriqui, it has been collected at Boquete as high 



