FAMILY TYRANNIDAE 409 



Measurements. — Males (14 from Veraguas, Colon, Canal Zone, 

 eastern Province of Panama, Darien, and San Bias), wing 84.9-87.3 

 (86.2). tail 63.8-71.2 (67.1). culmen from base 14.3-15.7 (14.9), 

 tarsus 18.1-18.9 (18.5) mm. 



Females (10 from Canal Zone, eastern Province of Panama, and 

 San Bias), wing 81.1-82.9 (82.0). tail 63.9-67.9 (65.6), culmen from 

 base 13.4-15.8 (14.7 ). tarsus 18.2-19.0 (18.5) mm. 



Resident. Found in the Tropical Zone, on the Pacific slope ; un- 

 common in eastern Chiriqui (San Felix) and Veraguas (Zapotillo, 

 Paracote ) ; recorded in the southern Canal Zone, and locally common 

 through eastern Province of Panama and Darien ; on the Caribbean 

 side fairly common from the Rio Indio, Colon (including the head- 

 waters in northern Code ) . and the Canal Zone eastward to the 

 Colombian boundary ; to 600 meters on Cerro Pirre. 



This species, one of South America, has its northern limit in 

 Panama, mainly in limited distribution in the eastern half of the 

 Republic. On the Pacific slope it is uncommon near Panama City. 

 To the west, Griscom collected it on the Rio San Lorenzo, Veraguas, 

 in 1924, and Aldrich took a pair February 15, 1932, at Paracote, 

 Veraguas, near the head of Golfo de Montijo. In western Veraguas 

 I found several and collected a male on May 19, 1953, on the Rio 

 Bubi beyond Zapotillo. Eisenmann in September 1958 saw it there 

 and near Las Lajas in eastern Chiriqui. The most western record is a 

 female that I collected on the Rio Dupi, west of San Felix, eastern 

 Chiriqui, February 18. 1956. The bird has not been recorded else- 

 where on this slope west of Panama City and the Canal Zone. On 

 the Atlantic side, in 1952, I found it in small number along the Rio 

 Indio, in the western sector of the Province of Colon, from near the 

 mouth inland to the foothills at El Uracillo, on the Caribbean slope 

 of Code. From here eastward it is fairly common through the Canal 

 Zone, eastern Colon, and presumably through the Comarca de San 

 Bias, where I found it at Mandinga in the west and Puerto Obaldia 

 on the Colombian boundary in the east. 



These flycatchers, one of several small- and medium-size kinds with 

 yellow breast, called Pecho AmariUo in Spanish, range in pastures, 

 fields, small clearings, or other open areas, usually in the vicinity of 

 water, where they rest quietly on open perches, turning the head 

 quickly from side to side and frequently expanding the breast 

 feathers so that the yellow color is conspicuous. Usually they are 

 found singly or in pairs, several being encountered in company only 

 when in the process of pairing. Then they may be quite vociferous, 



