Vireo huttoni, Cassin, Pr. A. N. Sc. Phila. 1851, 150 (Monterey, Cal.).—Ib. 1852, pl. i, fig. 1.—Baird, Birds N. Am. 1858, 339, pl. lxxviii, fig. 2; Rev. 357.—Sclater, P. Z. S. 1858, 302 (Oaxaca); 1862, 19 (La Parada).—Ib. Catal. 1861, 358, No. 256.—Cooper, Orn. Cal. 1, 1870, 121.
Sp. Char. (No. 3,725.) First quill rather less than half second, which about equals the tenth; third a little longer than seventh; fourth and fifth nearly equal, and longest. Tail slightly rounded, shorter than wings. Bill very small.
Vireo huttoni.
3725
Above olive-green; brightest behind, especially on rump and edging of tail, duller and more ashy towards and on top and sides of head and neck. Wings with two bands on coverts, and outer edges of innermost secondaries rather broadly olivaceous-white; other quills edged externally with olive-green, paler towards outer primary; internally with whitish. Lateral tail-feather edged externally with yellowish-white. Feathers of rump with much concealed yellowish-gray.
Under parts pale olivaceous-yellowish; purest behind, lightest on the throat and abdomen; the breast more olivaceous, the sides still deeper olive-green, the breast soiled with a slight buffy tinge. Axillars and crissum yellowish; the inside of wings whitish. Loral region and a narrow space around eye dull-yellowish, in faint contrast to the olive of head. Bill horn-color above, paler below; legs dusky.
Total length, 4.70; wing, 2.40; tail, 2.05; difference between tenth and longest quills, .43; exposed portion of first primary, .72, of second, 1.52, of longest, fourth, and fifth (measured from exposed base of first primary), 1.90; length of bill from forehead, .45, from nostril, .29, along gape, .60; tarsus, .72; middle toe and claw, .50, claw alone, .16; hind toe and claw, .45, claw alone, .22.
Hab. California and Western Mexico, to Oaxaca; La Parada (Scl.); Orizaba (alpine region, resident, Sumichr.).
The description just given is based upon the type specimen, probably in winter plumage. Spring specimens do not vary materially except in greater purity of white edgings of the feathers. Two Mexican specimens are rather larger, the wing measuring 2.50, the tail 2.30. No other differences are appreciable. In general the first primary is about half the second, sometimes rather less.
This species is readily distinguished from other Vireos, excepting V. modestus, which it greatly resembles in the small bill, form, coloration, and size; nor indeed is it easy to separate them. In modestus, however, the first quill is usually more than half the second, not less; the wing shorter, and less pointed; the tail longer. The upper parts are more uniform, not much brighter towards rump.