The Black-chinned Hummer 
No. 186 
Black-chinned Hummer 
A. O. U. No. 429. Archilochus alexandri (Boucier and Mulsant). 
Synonyms.— Sponge Hummer. Alexander'Hummer. 
Description. —Adult male: Upperparts, including central pair of tail-feathers, 
black, overlaid with shining bronzy green and blue-green; wing-quills and remaining 
rectrices purplish dusky; wing-quills sharply and diagonally truncated; tail double- 
rounded, the central pair of feathers broad and mildly acuminate, about .12 (4 mm) 
shorter than remaining feathers, which are narrow and sharply acuminate; gorget chiefly 
opaque velvety black, the posterior portion showing rich violet reflections; underparts 
chiefly dusky, on sides heavily overlaid with bronzy green with narrow white skirtings, 
elsewhere more relieved by white edging; white sometimes attaining clearness on middle 
of belly and (usually) sharply defining lower edge of gorget. Bill slender, straight, 
black; feet black. Adult female: Upperparts similar to those of male; but underparts 
chiefly sordid white; some faint tawny or dusky shading on sides; throat nearly immacu¬ 
late, or finely and sparingly speckled with dusky; tail quite different; central pair of 
feathers much as in male, the remaining pairs much broader, greenish at base, purplish 
black subterminally, broadly and decreasingly tipped with white, the outermost feather 
not noticeably emarginate on the inner web (as is the case with A. colubris ); primaries 
somewhat more rounded. Young male: Like adult female, but feathers of upperparts 
edged with pale buffy; and underparts more strongly suffused with pale brownish; throat 
more speckled. Young female: Like young male, but throat immaculate, or speckling 
reduced. Length of adult male about 88.9 (3.50); wing 42.7 (1.68); tail 25.4 (1.00); bill 
19.1 (- 75 )- Female, length up to 101.6 (4.00); wing 47.5 (1.87). 
Recognition Marks. —Pygmy size; black gorget of male distinctive; best field 
characters of female consist in lighter coloration of underparts, the reduced (or wanting) 
speckling of throat, and the more blended shading of sides of head and neck (or breast, 
when shaded). 
Nesting. — Nest: Typically, a deep, thin-walled cup with incurved edges, and 
composed exclusively of the pubescent down of young sycamore leaves, bound together 
with cobwebs. In default of this yellow material the bird will use white plant-downs, 
or compacted shreds variously decorated and lined. Placed on slender descending 
twigs or horizontal branches of bush or tree, usually at moderate heights and often 
over water. Eggs: 2; white, elliptical oval, often blunt-ended. Av. of 53 (U. S. N. M.) 
12.7 x 8.3 (.50 x .33). Season: May, June (at height about May 10th); one or, rarely, 
two broods. 
General Range. —Western North America, breeding in Sonoran and Transition 
zones from northern Lower California and northern Mexico north to British Columbia 
and northern Alberta, and from the Pacific Coast (save for the northwestern coastal 
strip) east to western Montana, western Colorado, and west-central Texas; wintering 
in western Mexico south to Guerrero. 
Distribution in California. —Common summer resident in Upper and Lower 
Sonoran zones practically throughout the State. Most abundant in San Diegan dis¬ 
trict. Not found in humid coastal section north of San Francisco Bay, nor upon the 
Santa Barbara Islands. Winters sparingly on the Colorado Desert (Grinnell). 
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