FAMILY TROCHILIDAE 263 



Measurements. — Males (10 from Panama), wing 56.3-60.4 (58.6), 

 tail 30.3-35.2 (33.3), oilmen from base 30.1-33.9 (31.9) mm. 



Females (10 from Panama and northwestern Colombia), wing 

 55.3-58.1 (56.8), tail 31.4-34.0 (32.9), culmen from base 31.0-33.9 

 (31.8) mm. 



Resident. Locally common in areas of forest ; found on the Pacific 

 slope from the headwaters of the Rio Pacora in the Cerro Azul east 

 through Darien ; on the Caribbean slope from the Canal Zone, near the 

 lower Rio Chagres, east through San Bias. 



Most of the birds from the lower Chagres Valley appear somewhat 

 intermediate toward the western race ventosus in a bronzy tint in the 

 dorsal plumage, but agree with darienensis otherwise. The population 

 while not typical is placed with the present form. 



These hummingbirds range in forest, mainly in undergrowth. 

 Stands of the abundant platanillos (Heliconia) are especially favored. 

 The flowers of these plants are visited constantly as a source of food. 

 Banana plantations where they border woodland also are favorite 

 haunts. Males sing at intervals, when they often seem noisy, but in 

 the main the birds are quiet. In the heavy shadows that they frequent 

 the dim light conceals their colors so that they may be barely seen. 

 The exception comes when they are displaying, or are excited, as then 

 the partly spread tail is vibrated rapidly with the white tip describing 

 a wide arc which immediately attracts the eye. 



I found them especially common in the forests covering the low 

 hills on the Quebrada Venado, back of the Cuna village Armila. Here 

 we released them daily from mist nets set for forest birds. 



PHAETHORNIS GUY CORUSCUS Bangs: Green Hermit, Ermitano 



Verde 



Phaethornis guy coruscus Bangs, Proc. New England Zool. Club, vol. 3, 

 January 30, 1902, p. 26. (Boquete, 1370 meters elevation, Chiriqui.) 



A large, dark-colored, long-tailed hermit with the back shining 

 bluish green, and the rump, upper tail coverts, and base of tail deep 

 blue. 



Description. — Length 145-155 mm. Adult male, above, including 

 most of wing coverts, bright metallic bluish green, duller on the 

 crown ; rump, upper tail coverts, and base of tail metallic blue, the 

 longer tail coverts terminally black, with the tip white ; distal half of 

 tail black, with the short, narrowed tips of the central pair gray, tipped 

 with white ; wing, including most of primary coverts, dull black with 

 a purplish sheen ; side of head distinctly black ; narrow line back of 



