S. platycercus. Above continuous metallic green; tail-feathers merely edged with rufous. Gorget purplish-red.
Wing, 1.90; tail, 1.40; bill (from forehead), .66. Gorget rich solferino-purple, the feathers grayish-white beneath the surface. Outer primary with its attenuated tip turned outward. Hab. Rocky Mountains and Middle Province of United States, south to Guatemala … var. platycercus.
Wing, 1.65; tail, 1.20; bill, .41. Gorget dull velvety-crimson, the feathers ochraceous beneath the surface. Outer primary apparently with its attenuated tip curved inward. Hab. Costa Rica … var. flammula.[116]
B. Feathers of the metallic gorget much elongated laterally.
S. rufus. Above chiefly rufous, overlaid by green (except in S. scintilla, which is almost wholly green above); tail-feathers rufous with a shaft-streak of dusky. Gorget fiery red. Attenuated tip of outer primary curved inwards.
Wing, 1.60; tail, 1.30; bill, .65. Rufous prevailing above; gorget very brilliant. Hab. Western Province of North America, from East Humboldt Mountains to the Pacific. North to Sitka, south to Mirador … var. rufus.
Wing, 1.35; tail, 1.00 to 1.10; bill, .42. Continuous green above; gorget not brilliant, but with a dusty appearance. Tail less graduated. Hab. Costa Rica and Chiriqui … var. scintilla.[117]
Selasphorus rufus, Swainson.
RUFOUS-BACKED HUMMING-BIRD.
Trochilus rufus, Gmelin, Syst. Nat. I, 1788, 497.—Aud. Orn. Biog. IV, 1838, 555, pl. ccclxxii. Selasphorus rufus, Swainson, F.-Bor. Am. II, 1831, 324.—Aud. Birds Am. IV, 1842, 200, pl. ccliv.—Baird, Birds N. Am. 1858, 134.—Cooper & Suckley, 164.—Dall & Bannister, Trans. Chicago Acad. I, 1869, 275 (Alaska).—Finsch, Abh. Nat. III, 1872, 29 (Alaska).—Cooper, Orn. Cal. 1, 1870, 355. Trochilus collaris, Lath. (Bonaparte). Trochilus sitkensis, Rathke (Bonaparte). Ornysmia sasin, Lesson (Bonaparte).