600 BIRDS OF THE REPUBLIC OF PANAMA — PART 3 



of mouth, including the inner face of the mandible and the tip of 

 the tongue, ivory-white ; inner surface of maxilla pale neutral gray ; 

 base of tongue and back of mouth cavity dusky neutral gray. 



Measurements. — Males (10 from northern Code, Colon, Province 

 of Panama, Darien, and San Bias), wing 55.7-59.5 (57.8), tail 

 39.7-45.8 (44.0), culmen from base 11.4-12.6 (12.0), tarsus 13.2- 

 15.4(14.0) mm. 



Females (10 from northern Code, Province of Panama, Canal 

 Zone, Darien, and San Bias), wing 52.3-58.1 (56.1), tail 39.4-44.1 

 (41.5), culmen from base 11.3-13.1 (12.1), tarsus 13.4-14.8 

 (14.2) mm. 



Weight J*, 10.3 grams (R. S. Crossin). 



Resident. Common, in forested areas, on the Pacific slope, from 

 the western sector of the Province of Panama (Cerro Campana) 

 east through Darien to the Colombian boundary ; on the Caribbean 

 side from the Rio Indio in western Colon (Chilar) and the northern 

 slope of Code (El Uracillo) through the northern Canal Zone, the 

 lower valley of the Rio Chagres, and the Comarca de San Bias 

 to Colombia ; to 600 meters on Cerro Pirre, and Cerro Tacarcuna 

 (La Laguna). Archipielago de las Perlas : Islas San Jose, Viveros, 

 and Rey. 



This is the most common and widely distributed of the races 

 found in the Republic, ranging in forests and also in thickets adjacent 

 to them. Though its subdued colors make it inconspicuous it may 

 attract attention by its chipping calls, as well as by flipping move- 

 ments of its wings. In the usual display one closed wing may be 

 raised vertically full length above the back, held motionless for a 

 brief second, and then lowered quickly to the resting position. The 

 action is so rapid that it may not be distinguished from ordinary 

 flitting movements unless the observer is looking directly at the 

 bird. While the bird may utter rapid, chipping calls when excited, 

 it is silent in this display. The action is like that of the Olive-striped 

 Flycatcher Mionectes olivaceus. They are found often alone, as 

 single individuals, but also may join the parties of other small birds 

 that forage in company in the forests. They pluck insects from 

 twigs and leaves in rapid, fluttering movements, and also feed exten- 

 sively on berries when available. 



Nest-building, incubation, and the care of the young are reported 

 as the work of the female alone, without assistance of the male, 

 with the breeding season extending from February to July. The 

 nest is a large, elongate, rounded structure, suspended at the end of 



