FAMILY ACCIPITRIDAE 189 



Immature in dark phase, two bands across the tail, and the tip 

 buflfy white; narrow tips of cinnamon above and below, and the 

 bases of the feathers of the under surface prominently white. Im- 

 mature, light phase, white to buffy white below, with a light band 

 across the hind neck, more or less barred with fuscous below ; 3 tail 

 bands of brownish gray. 



An immature bird in dark phase, taken at Juan Mina on January 

 14, 1955, had the iris dull Marguerite yellow; maxilla and anterior 

 half of cutting edge of mandible dusky neutral gray ; rest of mandible, 

 anterior one- fourth of loral space, and cere, dull yellowish green ; 

 remainder of loral space, and bare eye ring, light vetiver green ; gape, 



Fig. 40. — Head of hook-billed kite, gavilan piquiganchudo, Chondrohierax unci" 



naius uncinatus. 



and a bare spot above lores, orange; tarsus and toes yellow; claws 

 black. An adult in complete dark phase taken at 200 meters eleva- 

 tion in the Cerro Azul along the upper Rio Pacora differed in having 

 the iris bluish gray. 



Measurements. — Males (6 from Panama and Colombia), wing 272- 

 290 (281), tail 177-195 (185), culmen from cere 26.7-31.5 (29.7), 

 tarsus 34.6-39.9 (37.1) mm. 



Females (5 from Panama and Colombia), wing 272-285 (280), 

 tail 179-193 (186), culmen from cere 30.0-30.9 (30.3), tarsus 33.5- 

 39.5 (36.5) mm. 



Resident. In forested areas in the tropical and lower subtropical 

 zones. Recorded to date from Chiriqui (Boquete, El Volcan) ; 

 Veraguas (Arce specimen without locality) ; eastern Panama (lower 

 slopes of the Cerro Azul) ; Isla Saboga, and Isia Pedro Gonzalez, 



