FAMILY TYRANNIDAE 431 



In Panama these flycatchers inhabit tree cover at the borders of 

 fields and pastures, the inner margins of mangrove swamps, and 

 scattered open growth. They penetrate heavily forested areas mainly 

 along the open courses of larger streams. They may remain in areas 

 of shifting agriculture, in the quickly established second growth that 

 fills cleared areas used temporarily for plantations. 



They range alone, or in the nesting season in pairs, though often 

 in sufficient abundance so that they are encountered widespread in 

 such haunts. 



The call, as I have heard it in Panama, is not loud, but rather high- 

 pitched, uttered slowly, represented in my field notes as whee-ee-ee, 

 a sound uttered by both sexes usually without especial emphasis. In 

 early morning and evening the notes may be repeated steadily for 

 several minutes as the form of song usual to other species in this 

 family. They are quiet birds that rest on slightly elevated perches, 

 often sheltered partly by leaves so that their presence may be known 

 only casually from their low calls. While occasionally belligerent, 

 they are not as violently so as some related species of the family. Their 

 food is largely insects, taken in the air or picked from leaves and 

 twigs as they move about. They also come regularly in company 

 with other forest birds to eat the berries found in feeding trees. 



MYIARCHUS TUBERCULIFER BANGSI Nelson 



Myiarchns hmrcncci bangsi Nelson, Proc. Biol. Soc. Washington, vol. 17, 

 March 10, 1904, p. 45. (Boquete, Chiriqui.) 



Characters. — Crown somewhat dull black ; back darker ; primaries, 

 and in some the outer tail feathers, edged with cinnamon-bufif to 

 cinnamon-rufous. 



A female, taken at Puerto Armuelles, Chiriqui, February 11. 1966, 

 had the iris dark brown ; maxilla and tip of mandible fuscous-brown ; 

 base of mandible light wood brown ; tarsus and toes fuscous-black ; 

 claws black. 



Measurements. — Males (10 from Chiriqui and Bocas del Toro), 

 wing 76.0-82.6 (79.2), tail 69.2-78.3 (72.3), culmen from base 

 18.6-21.4 (20.3), tarsus 19.1-20.1 (19.5) mm. 



Females (10 from Chiriqui and Bocas del Toro), wing 73.2-78.7 

 (75.2), tail 66.3-70.7 (68.6), culmen from base 18.6-20.9 (19.8), 

 tarsus 18.3-19.7 (19.0) mm. 



Resident. Locally common and widely distributed on the Pacific 

 slope in Chiriqui and Veraguas, including the western side and the 

 southeastern tip of the Azuero Peninsula ; on the Caribbean slope 



