328 BIRDS OF THE REPUBLIC OF PANAMA PART 2 



of the population groups is evident, so that it has been appropriate 

 to synonomize some of these earlier proposals. In the outline that 

 follows, the six subspecies that have been described are reduced to 

 four, namely, an eastern and a western race, with an intermediate 

 group that connects them, and one in addition on the Pearl Islands 

 and the Taboga group of islets. 



These hummingbirds range in open forests, and shelter also in low 

 rastrojo in abandoned fields. They feed constantly at flowers, espe- 

 cially on those of shrubs and trees, and where blossoms are freshly 

 open, the birds may gather in numbers with others of their family. 

 They are active in movement, always pugnacious, even attacking large 

 bees that come too near. In such congregations the present species 

 is easily identified by the white of the lower breast and abdomen, 

 which is in abrupt contrast with the green of the foreneck and chest. 

 Occasionally, I have seen them hawking small diptera in the air. 

 The stomachs of those that I have examined have been filled with 

 remains of tiny flies, hymenoptera, and spiders. 



AMAZILIA EDWARD NIVEOVENTER (Gould) 



Trochilus ( ?) niveoventer Gould, Proc. Zool. Soc. London, pt. 18, 1850 



(February 28, 1851), p. 164. (Near David, Chiriqui, Panama.) 



Amasilia edward ludibunda Wetmore, Smithsonian Misc. Coll., vol. 121, no. 2, 

 December 2, 1952, p. 16. (Pese, Herrera, Panama.) 



Characters. — Tail blue-black, in some with a sheen of reddish 

 brown ; back duller, less coppery bronze-green ; under tail coverts 

 mainly dusky gray centrally, edged broadly with white. 



Measurements. — Males (12 from Isla Coiba, Chiriqui, and 

 Veraguas), wing 52.9-56.7 (54.3), tail 28.3-30.7 (29.4), culmen from 

 base 18.0-19.8 (19.0) mm. 



Females (10 from Isla Coiba, Chiriqui, Veraguas, and Herrera), 

 wing 51.0-54.3 (52.5), tail 27.7-30.5 (29.2), culmen from base 

 18.7-20.5 (19.7) mm. 



Weight, 12 males 4.97+0.10; 8 females 4.43 ±0.08 grams (Hart- 

 man, Auk, 1954, p. 468). 



A male, taken at Las Palmitas, Los Santos, January 24, 1962, 

 had the iris very dark brown ; maxilla and tip of mandible black ; 

 distal end of tarsus, toes, and claws black. 



Resident. Locally common from the Costa Rican boundary in 

 Chiriqui east on the Pacific slope to western Code and the Azuero 

 Peninsula, from sea level in the lowlands to 1,675 meters elevation 

 on Volcan de Chiriqui ; Bocas del Toro ; Isla Coiba. 



