172 Genera of Humming Birds. 



This rare and peculiar species was discovered in Veragua. 

 by Mr. Endrés. 



I have killed it at Naranjo, Costa Rica, in April, 1877. 



My other specimens were collected in Veragua by Arce. 



•GENUS LXXIII. Elvira, Muls. and Verr., Class, Troch., 



1865, p. 32. 



TYPE : T. chionurus, Gould. 



Bill shorter than the head, straight, with tip slightly curved. 

 Nostrils slightly exposed. Wings narrow, pointed, longer 

 than the tail. Tail slightly rounded. Tarsi clothed. Sexes 

 unlike. 



Habitat. — Costa Rica and Veragua. 



248. Elvira chionura, Gould, P.Z.S., 1850, p. 162. 



Leucippus chionurus, Reich., Aufz. der Col., 1853, p. 11. 



Thaumantias chionura, Bon., Rev. and Mag. Zool., 1854, 

 P- 255- 



Elvira chionura, Muls., Hist. Nat. Ois. Mou., 1874, t. i., 

 p. 266. 



White-tailed Emerald, Gould, Mon. Troch., vol. v., p. 300. 



l'Elvire à queue d'un blanc de neige, Muls., Hist. Nat. Ois. 

 Mou., 1874, t. i., p. 267. 



Habitat. — Costa Rica and Veragua. 



Male. — Upperside shining golden-green, sometimes dark 

 green. Median rectrices bronzy-green, lateral white with 

 black tips. Underside metallic emerald-green with golden 

 reflections. Centre of abdomen and undertail-coverts pure 

 white, some bronze feathers on undertail-coverts feathers in 

 some specimens. Wings purplish-brown. Maxilla black. 

 Mandible flesh colour with black tip. 



Total length, 3§in. Wing, 2. Tail, if. Culmen, f. 



Female. — Upperside shining-green. Median rectrices 

 bronzy-green, the one next to it on each side, bronze-green 

 with black tips, remainder white with subterminal black bar, 

 and white tips. Underside grayish-white with green feathers 

 on sides of breast and flanks. Wings purple-brown. Bill 

 black. 



Total length, 3fin. Wing, i|-. Tail, if. Culmen, |-. 



