HUMMINGBIRDS: COSTA HUMMINGBIRD 
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saliva’’ and coated with spider web, occasionally with small leaves or oak blossoms 
on outer walls. Eggs: 2 or 3, white. 
Food. —Small insects and honey from blooming flowers and shrubs, as the tree 
tobacco. 
General Habits. —The Black-chinned Hummingbird is said by 
Mr. Robert Woods to be “ typical of the foothills and canyons of the 
less humid portions of the West.” When sitting sunning himself on an 
oak twig he seems a very quiet body, for one of his intense, hot-blooded 
clan, but when showing off in courtship he has a pretty little animated 
aerial dance, swinging back and forth before his prospective seated 
mate, throwing himself back at the end of his line by a quick spread 
of the tail. His shuttling, as Mr. Woods explains, takes the form of 
a narrow figure 8 lying on one side (1927, p. 303). Like other hum¬ 
mingbirds in the nesting season, he will also dive from a height with 
gorget puffed out and tail spread spectacularly, making a loud whirring 
sound. 
In nest building the females go through the usual process of molding 
the inside of the cup, molding like a potter shaping his cup, twirling 
tremulously around against the sides, sometimes pressing hard enough to 
ruffle up the feathers of the breast. To round the outside, the tiny 
builder will sit on the rim and lean over, smoothing the sides with her 
bill, often with the same tremulous motion. When wanting to turn 
around in the nest she will rise prettily on softly whirring wings. 
Two and sometimes probably three broods are raised in a season. 
A Black-chin that Mr. N. K. Carpenter knew of for four successive 
years built a nest on an electric wire within six inches of a porch light. 
The current was on every evening but the light did not seem to disturb 
the sensible bird, who reared one family each season (1903, p. 20). 
Two nests were found by Mr. Bailey, one in the great west entrance 
to the Carlsbad Cave and the other under the arched entrance to the 
Bighorn Cave, where the White-throated Swifts nested. 
Additional Literature.—Grinnell, Joseph, Univ. Calif., Pubk Zool., vol. 12, 
no. 4, 143-145, 1914.— Holland, H. M., Condor, XVIII, 31, 1916 (unusual nest).— 
Wueste, R. C., Condor, IV, 39-40, 1902 (nesting). 
COSTA HUMMINGBIRD: Calypte c6stae (Bourcier) 
Description. — Male: Length 2.7-3.2 inches, wing 1.7-1.9, tail 1.1, bill -6. 
Female: Length 3.5-3.7 inches, wing 1.7, tail 1, bill .7. Adult male with tail slight \y 
forked, adult female with tail nearly rounded; outside tail feathers in male very narrow. 
Adult male: Entire head , gorget , and long flaring ruff glittering metallic violet or ame¬ 
thyst-purple, changing to black, blue, green, or magenta in varying lights; rest of 
upperparts, including middle tail feathers, dull metallic bronze-green; lateral tail 
feathers grayish or brownish, glossed with green; wing quills dusky, faintly glossed 
with purplish; underparts whitish, belly gray, glossed with golden-green. Adult 
female: Entire upperparts, including middle tail feathers, dull metallic bronze-green, 
other tail feathers green or gray, black-tipped or white-tipped; underparts brownish 
