588 BIRDS OF THE REPUBLIC OF PANAMA PART 3 



in Darien or San Bias, it is probable that it may occur there, since a 

 series in the U.S. National Museum from northwestern Colombia in 

 the Departments of Antioquia and western Bolivar are like the bird 

 of Central Panama. Farther east in central and eastern Bolivar, east 

 through Magdalena to northwestern Venezuela where they become 

 faintly paler and slightly more brightly colored, they are referred 

 to as the race diversus described by Todd. 



LEPTOPOGON AMAUROCEPHALUS IDIUS Wetmore 



Leptopogon amauroccphalus idius Wetmore, Smithsonian Misc. Coll., vol. 134, 

 no. 9, July 8, 1957. p. 71. (Isla Coiba, Panama.) 



Characters. — Generally similar to L.a. faustus, but decidedly grayer 

 throughout ; much paler yellow on lower breast and abdomen ; more 

 grayish green above ; wing bars paler, less rufescent ; under wing 

 coverts paler, less yellow. 



An adult male, collected January 31, 1956, 4 miles northwest of 

 La Central, Isla Coiba, had the iris light brownish yellow ; maxilla 

 and tip of mandible dusky neutral gray; base of mandible dull 

 Marguerite yellow ; tarsus and toes neutral gray ; claws fuscous. 



Measurements. — Males (2 specimens), wing 64.3, 65.3, tail 57.4, 

 57.5, culmen from base 13.7, 13.8, tarsus 14.4, 14.5 mm. (The first 

 measurement in each case is that of the type.) 



Females, none available for measurement. 



Resident. Rather rare ; restricted to Isla Coiba, off the Pacific coast 

 of western Panama. 



During daily field work on the island January 6 to February 6, 

 1956, I saw this bird on two occasions. As the island was heavily 

 forested, a bird of this type that is not common may be encountered 

 more or less by chance. On the first occasion, on January 31, two 

 moved rather slowly through the middle branches in gallery forest 

 at an elevation of about 150 meters. Apparently this was a pair. The 

 one that I collected, which proved to be a male in breeding condition, 

 at intervals trembled its partly opened wings while it uttered a low 

 call, pree-ee-ee-ee. On February 3, another adult male in breeding 

 condition was taken in heavy forest in this same area. In the subdued 

 light under the heavy stand of trees it moved quietly through the 

 lower branches at a level slightly above the undergrowth. Dr. Eisen- 

 mann notes that he and E. S. Morton captured one in a mist net on 

 October 9, 1965. "in heavily cutover, rather open woodland." 



The small size of the tarsus in the two specimens taken was noted 

 during my original studies. While an occasional specimen of L. a. 



