404 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 
[Eupherusa] chionura Staton, Cat. Troch., 1897, 21. 
[Polytmus] chionurus Gray, Hand-list, i, 1869, 129, no. 1637. 
Elvira chionura Mutsant and Verreaux, Hist. Nat. Ois.-Mouch., i, livr. 4, 
1874, 266; iv, livr. 3, 1878, 179.—Euu1or, Classif. and Synop. Troch., 1879, 
210.—ZeLEeDOn, Cat. Aves de Costa Rica, 1882, 21; Anal. Mus. Nac. Costa 
Rica, i, 1887, 122.—Satvin, Cat. Birds Brit. Mus., xvi, 1892, 74 (Costa 
Rica; Chiriquf and Calovévora, Verdgua)—Satvin and Gopman, Biol. 
Centr.-Am., Aves, ii, 1892, 273—Bovucarp, The Hum. Bird, ii, 1892, 81 
(Verégua); Gen. Hum. Birds, 1894, 172.—Baneas, Proc. New Engl. Zool. 
Club, iii, 1902, 29 (Boquete and Volcan de Chiriquf, 4,000-7,700 ft.); Auk, 
xxiv, 1907, 296 (Boruca, Costa Rica).—Carriker, Ann. Carnegie Mus., vi, 
1910, 535 (Costa Rica). 
[Elvira] chionura Muusant, Ann. Soc. Linn. Lyon, xxii, 1876, 205.—SHarpz, 
Hand-list, ii, 1900, 116. 
Elvira] chionura Hartert, Das Tierreich, Troch., 1900, 90 (monogr.). 
Eupherusa niveicauda Lawrence, Ann. Lyc. Nat. Hist. N. Y., viii, 1867, 134 
(Dota, Costa Rica; coll. U. 8. Nat. Mus.). 
ELVIRA CUPREICEPS (Lawrence). 
COPPERY-HEADED EMERALD. 
Similar to E. chionura, but bill distinctly decurved and adult 
male with upper tail-coverts bright copper-bronze, pileum and 
middle rectrices bronze instead of green, no white on abdomen, and 
lateral rectrices tipped (less extensively) with light gray instead 
of black. 
Adult male.—Pileum dull coppery bronze; hindneck, back, scapu- 
lars, rump, and wing-coverts bronze-green; upper tail-coverts bright 
coppery bronze; middle pair of rectrices bronze (much less coppery 
than upper tail-coverts); four outer rectrices (on each side) pure 
white, the three outer tipped with pale gray, the fourth tipped (more 
abruptly) with black; remiges dusky purplish brown, the inner 
secondaries mostly bronze-green; under parts bright yellowish me- 
tallic green, the under tail-coverts pure white, the anal tufts grayish 
white; maxilla black; mandible pale (flesh color in life?), dusky 
terminally; iris dark brown; feet grayish brown (in dried skins); 
length (skins), 74-79 (77); wing, 46-51 (48.4); tail, 24-27 (25.4); 
culmen, 13.5-15 (14.1).¢ 
Adult female.—Above metallic green (less bronzy than in adult 
male), duller on pileum; upper tail-coverts and middle pair of 
rectrices bright bronze (the former usually more coppery); four outer 
rectrices white with a V-shaped subterminal bar of gray or dusky, 
the fourth tipped with black or black and gray and edged for ter- 
minal half (more or less) with blackish; remiges as in adult male; 
under parts dull white or grayish white, passing into pure white 
posteriorly, the sides more or less (sometimes extensively)? spotted 
@ Ten specimens. 
6 Occasionally the green spotting extends across chest or breast. 
