Note 77 — Family VIREONIDÆ.—The Vireos.

Vireosylvia propinqua, Baird, Rev. 1865, p. 348. This appears to be merely a permanent resident race of solitarius, which itself visits Guatemala only in winter. Closely resembling the latter, it differs essentially in the respects pointed out above. The difference in coloration is produced by a shifting, as it were, toward the head of the yellow and olive, leaving the upper tail-coverts clear ash, and the lower pure white, and encroaching upon the ash anteriorly to the crown and ear-coverts, and the white alongside of the throat. In the V. plumbeus these tints are simply almost entirely removed, leaving clear ash and pure white, with a tinge, however, of olive on the rump and of yellow on the sides. In V. cassini the tints are darkened and browned by the peculiar influence of the region where found, there being neither clear ash, nor olive-green, nor pure yellow or white, in the plumage.