l8o BIRDS OF THE REPUBLIC OF PANAMA PART 4 



tzeet" (Ridgely, 1976, p. 279). Eisenmann (in lift.) has heard nasal 

 twanging or mewing notes, sounding like twee, twee, twee and peeoo, 

 peeoo, peeoo. 



POLIOPTILA PLUMBEA SUPERCILIARIS Lawrence 



Polioptila superciliaris Lawrence, 1861, Ann. Lyc. Nat. Hist. New York, 7, p. 304. 

 (New Grenada, Isthmus of Panamas Atlantic slope, near Panama Railroad; 

 fide Lawrence loc. ext. p. 322.) 



Characters. — Dorsal surface bluish gray; lower foreneck and breast 

 whitish. 



A male collected at Las Palmitas, Los Santos, on January 25, 1962, 

 had the iris dark reddish brown; base of mandible neutral gray; rest 

 of bill black; tarsus and toes dusky neutral gray; claws black. 



Measurements. — Males (10 from Los Santos, Herrera, Code, and 

 Province of Panama), wing 43.5-48.6 (45.8), tail 36.2-46.3 (42.1), 

 culmen from base 10.1-13.3 (12.2, average of 9), tarsus 14.7-17.3 

 (16.1) mm. 



Females (10 from Los Santos, Herrera, Veraguas, Province of Pan- 

 ama, Darien), wing 41.0-46.5 (44.1), tail 35.3-43.8 (39.9), culmen 

 from base 11.7-13.3 (12.2, average of 9), tarsus 15.3-16.7 (15.9) mm. 



Resident. Widespread and fairly common in a variety of mainland 

 habitats including forest (although usually at breaks and edges), 

 second-growth woodland, and scrub in semi-arid as well as humid areas. 

 The Tropical Gnatcatcher is usually seen from sea level to about 1200 

 m, the highest elevational record being a female collected on March 10, 

 1951, by Frank Hartman at 1230 m on Cerro Pando, Chiriqui. Aldrich 

 and Bole (Scient. Pub. Cleveland Mus. Nat. Hist., vol. 7, 1937, p. 23) 

 found it one of the commoner birds in brushy scrub and forest mar- 

 gins of the Tropical Zone, arid division (sea level to 300 m) on the 

 western side of the Azuero Peninsula. Eisenmann (Smiths. Misc. 

 Coll., vol. 117, no. 5, 1952, p. 48) calls it "not common" on Barro 

 Colorado Island in the Canal Zone. He has found it in many localities 

 in the Canal Zone and in adjacent parts of the Province of Panama. 



The Smithsonian has specimens from nearly every section of the 

 Republic, from Almirante, Bocas del Toro, and Puerto Armuelles, 

 Chiriqui, in the west, to Jaque in eastern Darien. P. p. superciliaris has 

 been collected in Veraguas at Puerto Vidal, at the mouth of the Rio 

 Vira, in the extreme southwest, and at Sona; in Herrera at Parita, 

 Portobelillo, Santa Maria, and La Cabuya; in Los Santos at Las 

 Palmitas and Pedasi; in Code at El Roble; in the Province of Panama 

 from Bejuco in the west to Chiman in the east; and in Darien from 



