534 BIRDS OF THE REPUBLIC OF PANAMA PART 3 



on the Caribbean side, or to the eastern section of the Pacific slope. 

 They are found usually low down, but may come also, at least briefly, 

 into taller trees. They may also appear in the inland border of man- 

 grove swamps. Attention may be drawn to them by their chattering, 

 trilling calls, after which they may be identified by their plain pattern 

 of coloration, their slender form, and relatively long tail. Their food, 

 gleaned in their active movement through the open branches, is com- 

 posed of small insects. A typical stomach of one taken near Corozal, 

 Canal Zone, contained fine bits of half a dozen species of tiny beetles, 

 small hymenoptera, and heteroptera. 



Though as a species these birds, in addition to the area described 

 in Panama, range widely through northern Colombia and Venezuela 

 to Guyana, there is as yet no definite information on their nesting. 



The subspecies wilcoxi was named by Griscom "in honor of Mr. 

 A. L. Wilcox, president of the Tropical Forest Products Company," 

 in recognition of his assistance during field work in the forests of 

 southern Veraguas. 



PERISSOTRICCUS ATRICAPILLUS (Lawrence): Black-capped 

 Pygmy-tyrant, Moscareta Pigmea Gorranegra 



Figure 45 



Orchilns atricapillus Lawrence, Ibis, ser. 3, vol. 5, July 1875, p. 385. (Angostura, 

 Cartago, Costa Rica.) 



Tiny, with very short tail ; crown black ; back greenish. 



Description. — Length 60-70 mm ; tail less than half as long as wing. 

 Adult male, crown black, becoming slate posteriorly ; hindneck and 

 side of head slate-gray ; back, scapulars, rump, upper tail coverts, and 

 lesser wing coverts bright olive-green ; wings slate-black, with olive- 

 green to yellowish edgings, these becoming broader and yellower on 

 inner secondaries ; greater and middle coverts tipped with olive-green ; 

 lores with a black spot adjacent to eye, and a white line extending 

 back to connect with a narrower white orbital circle ; f oreneck and 

 center of upper breast white, with the latter area faintly lined with 

 gray ; sides gray ; tibia dusky, tipped with white ; posterior under 

 parts, flanks, axillars, and under wing coverts pale yellow ; inner 

 margins of under side of wing dull white. 



Adult female and juvenile similar, but with crown duller, ranging 

 from dull black on the forehead to dusky slate posteriorly. 



A male, taken at Puerto Obaldia, San Bias, March 16, 1963, had 

 the iris dark brown ; base of gonys and extreme tip of mandible white ; 

 rest of bill black ; tarsus and toes pale brown ; claws somewhat darker. 



