Vireo cassini, Xantus, Pr. A. N. S. Phil. May, 1858, 117.—Baird, Birds N. Am. 1858, 340, pl. lxxviii, fig. 1; Review Am. B. I , 1865, 347 (sub V. solitaria), Ridgway.
Sp. Char. Third and fourth quills nearly equal, fifth shorter, second longer than seventh. Spurious primary very narrow, falcate, acute; less than one third the second quill, and a little more than one fourth the third. Above, including edges of wing and tail-feathers, clear olive-green, becoming dusky ashy on the top and sides of head. Beneath fulvous-white, tinged with ill-defined olive-green on the sides (scarcely on the crissum). Two broad bands on the wing-coverts and the outer edges of the innermost secondaries greenish-white; the outer edge of outer tail-feather, with a broad ring round
the eye, extending to a frontal band, dull white. Length about 5 inches; wing, 2.75; tail, 2.30.
Hab. Fort Tejon, Cal. (Xantus); West Humboldt Mountains, Nevada (Ridgway).
Since the type of this variety was obtained, two other specimens (Nos. 53,418 ♀ and 53,419 ♂, September, 1867; R. Ridgway) have been secured by the United States Geological Survey of the 40th Parallel, in command of Mr. Clarence King, in the West Humboldt Mountains, Nevada. These specimens are even more different from true solitarius than is the type of this race, showing that it is really distinct, as a variety. In the same thickets at the same season, perfectly typical specimens of V. solitarius were obtained; the latter having, no doubt, come from their more northern summer home on their passage southward into Mexico.
In the Humboldt Mountain specimens the crown shows no trace of ash, and is even darker and more brownish than the back. In fact, the relation of the V. cassini to V. solitaria is an almost exact parallel to that of V. josephæ to V. gilvus, as far as coloration is concerned, in each case the extreme being widely different, but connected by specimens showing intermediate characters.
Nothing is known of the habits of this race.
Lanivireo solitarius, var. plumbeus, Coues.
LEAD-COLORED VIREO.
Vireosylvia plumbea, Coues, Pr. A. N. Sc. Phila. 1866 (Fort Whipple, near Prescott, Arizona).—Cooper, Orn. Cal. 1, 1870, 119.—Elliot, Illust. Birds N. A. I, vii. V. (Lanivireo) plumbea, Baird, Rev. 349.