462 SYSTEM A TIC SYNOPSIS. — PICABI^ — CYPSELIFOBMES. 
Fig. 305. — Alexander Hum- 
ming-bird, tail of young and 9 > 
nat. size. (From Elliot.) 
dusky; tail double-rounded, the central feathers shorter than the next, the lateral then gradu- 
ated; all broader than in $ to near the end, then rapidly nan-owing with concave inner margin; 
tail with black bars, and the lateral feathers white-tipped ; no rufous on tail in either sex. 
Length of $ 3.25; extent 5.00; wing 1.75 ; tail 1.25 ; bill 0.66. 9 smaller: length 2.80; 
extent 4.60. Eastern N. Am., especially U. S., abundant in summer, generally seen hovering 
about flowers, sometimes in flocks. Feeds on insects, and the sweets of flowers. Nest a beau- 
tiful structure, of downy substances, stuccoed with lichens outside; eggs two, white, 0.50 
X0.35. 
410. T. alexan'dri. (To Alexander. Fig. 305.) Alexander Humming-bird. Size and general 
appearance of T. coluhris. $ : Tail double-rounded, i. e., centrally emarginate, laterally 
rounded: central emargination about 0.10, lateral graduation 
more ; the feathers all acuminate, and whole-colored. Upper 
parts, including two middle tail-feathers, as in T. coluhris. 
Gorget opaque velvety black, only posteriorly glittering with 
violet, sapphire and emerald. Other under parts whitish, green 
on sides. Length 3.25 ; wing 1.75 ; tail 1.25 ; bill from frontal 
feathers 0.75. 9- Tail diff"erent from that of ^, both in shape 
and color; simply slightly rounded (without appreciable central 
emargination), the lateral feathers scarcely acuminate; middle 
feathers like the back, darkening at ends; others with broad purplish-black space near end, 
and white-tipped; thus so closely resembling coluhris 9 that the lack of decided emargina- 
tion of the tail is the principal character. No gorget, the throat whitish with dusky specks. 
California, Utah, Arizona, and probably other portions of SW. U. S. 
137. SELAS'PHORUS. (Gr. creAay, light ; ^opoy, bearing.) Lightning Hummers. Bill slender 
and subulate; frontal feathers covering nasal scale. Tail in J" 9 graduated or rounded, not 
forked, and extensively rufous or tipped with white. The central much broader than the lateral 
feathers. Details of shapes of the feathers varying with the species, and with the sexes (see 
descriptions, and figs. 306, 307). Outer primary, or two outer ones, of ^ abruptly attenuate, 
the end bowed ; inner six primaries not abruptly narrower than those further outward. 
Tarsi naked. BiU black. A metallic gorget in ^, little or not produced into a rufi*; no 
scales on crown. 9 lacking the gorget, and tail white-tipped. 
411. S. ru^fus. (Lat. rufus, reddish.) Ked-backed Rufous Humming-bird. Nootka Hum- 
ming-bird. ^ : No metallic scales on crown. Gorget glancing coppery-red, somewhat pro- 
longed into a rufi". Tail cuneate ; middle pair of feathers broad, narrowing rather suddenly to 
a point. Next pair broad, nicked or emarginate near end (fig. 306). 
Next three pairs successively narrowing gradually, but not even the outer 
becoming acicular. Two outer primaries narrow, falcate, gradually very 
acute, the ends bowed inward. General color above and below cinnamon- 
red, becoming more or less green on the crown, and sometimes flaked 
with green on the back, fading to white on the belly. Tail-feathers 
cinnamon-red, deepening to dusky-purplish at ends. Quills dusky- 
purplish. Length about 3.50; wing 1.50-1.67, averaging 1.60; tail 
L30; bill 0.65. 9 showing the characters of the tail and wing, but less 
plainly. Coloration extensively rufous, but overlaid with green; no 
gorget, replaced by a few dusky-greenish feathers ; under parts exten- 
sively M^hite, but shaded with cinnamon on the sides and crissum. Middle tail-feathers glossed 
with greenish, darkening to black at end, and usually touched with cinnamon at base; other 
tail-feathers extensively rufous, then black, finally white-tipped. Length 3,20; wing 1.70; 
tail 1.20. (On comparing 9 rufus with 9 platycercus, a great difference in the size of the 
outer feather is observable; in rufus this feather is only 0.12 broad, and under 1.00 long; in 
Fig. 306. Tail of S. 
rufus, nat. size. 
