BIRDS OF NORTH AND MIDDLE AMERICA. 401 
Eupherusa nigriventris LawRrEencE, Proc. Ac. Nat. Sci. Phila., 1867, 232 (Costa 
Rica; coll. U. 8. Nat. Mus.); Ann. Lyc. N. Y., ix, 1868, 127 (Costa Rica).— 
Frantzius, Journ. fir Orn., 1869, 317 (Costa Rica)—Sanvin, Proc. Zool. 
Soc. Lond., 1870, 210 (Cordillera del Chucu, Verdgua; descr. female),— 
Mutsant and VERREAuUX, Hist. Nat. Ois.-Mouch., i, livr. 4, 1874, 270, 
pl. 23 (Costa Rica); iv, livr. 3, 1878, 179 (Cordillera del Chucu; descr. 
female) —Satvin and Gopman, Biol. Centr.-Am., Aves, ii, 1892, pl. 57, 
figs. 3, 4. 
[Euphrerusa] nigriventris Mutsant, Ann. Soc. Linn. Lyon, xxii, 1876, 205; Cat. 
Ois.-Mouch, 1875, 6. 
[Eupherusa] nigriventris Stuon, Cat. Troch., 1897, 21. 
Callipharus nigriventris Exziot, Classif. and Synop. Troch., 1879, 211.—Ze.ep6n, 
Cat. Aves de Costa Rica, 1882, 21; Anal. Mus. Nac. Costa Rica, i, 1887, 122 
(Naranjo de Cartago, Costa Rica).—SHarPs, in Gould’s Suppl. Troch., 1887, 
pl. 54.—Satvin, Cat. Birds Brit. Mus., xvi, 1892, 67 (Cordillera del Chucu 
and Calobre, Verdgua; Costa Rica).—Satvin and Gopmay, Biol. Centr.-Am., 
Aves, ii, 1892, 270 (Cervantes and Peorsnada, Costa Rica, etc.).—Boucarp, 
The Hum. Bird, ii, 1892, 81 (Veragua); Gen. Hum. Birds, 1894, 171 (Naranjo, 
Costa Rica; Veragua). 
[Polytmus] nigriventris Gray, Hand-list, i, 1869, 133, no. 1702. 
[Thaumatias] nigriventris ScLaTeR and Satvin, Nom. Av. Neotr., 1873, 92. 
Ellvira] nigriventris Hartert, Das Tierreich, Troch., 1900, 90 (monogr.). 
Elvira nigriventris Banas, Proc. New Engl. Zool. Club, iii, 1902, 29 (Volc4n de 
Chiriqui, 6,000-7,000 ft.).—Carrixer, Ann. Carnegie Mus., vi, 1910, 534 
(Caribbean slope, Costa Rica).—Frrry, Pub. 146, Field Mus. N. H., crm. 
ser., i, no. 6, 1910, 263 (Coliblanco, Costa Rica). 
[Elvira] nigriventris SHarPE, Hand-list, ii, 1900, 116. 
Genus ELVIRA Mulsant and Verreaux. 
Elvira Mutsant and VeRREAUX, Classif. Troch., 1865, 32. (Type, Trochilus 
(Thaumatias) chionura Gould.) 
Lawrencius (not Lawrencia Ridgway, 1886) Boucarp, Gen. Hum. Birds (in 
Humming Bird, iv, pt. 3), sig. s, Sept., 1894, 173. (Type, Hupherusa cuprei- 
ceps Lawrence.) 
Small Trochilide (length about 75 mm.) closely resembling Euphe- 
rusa, but with maxillary tomium entirely smooth,? the bill relatively 
smaller (rather shorter than head), tail double-rounded or emarginate 
and secondaries green and dusky, instead of cinnamon-rufous. 
Bill rather shorter than head, nearly terete, straight (E. chionura) 
or distinctly decurved (E. cupreiceps) ; culmen rounded except basally, 
where contracted into a distinct ridge; tomia smooth;* mandible with 
lateral median groove indistinct. Nasal operculum rather narrow, 
tumid, mostly unfeathered, the frontal feathering extending on each 
side of culmen to about the middle of nasal operculi. Tarsus feath- 
ered; middle and inner toes about equal in length, the outer slightly 
shorter, the hallux slightly shorter than outer toe. Wing decidedly 
more than three times as long as exposed culmen, the outermost 
@ Apparently, however, sometimes there are, when a magnifying glass is used, 
faint indications of serrations. 
81255°—Bull. 50—11——26 
