_Eggs._--The measurements of 16 eggs average 18.5 by 13.6 millimeters; the eggs showing the four extremes measure =19.8= by 14.0, 19.5 by =14.4=, =17.3= by 13.9, and 17.6 by =12.4= millimeters (Harris). DENDROICA NIGRESCENS (Townsend) BLACK-THROATED GRAY WARBLER PLATE 35 HABITS The black-throated gray warbler is neatly dressed in gray-black and white, with only a tiny spot of bright yellow in front of the eye. Its breeding range extends from southern British Columbia, Nevada, northern Utah, and northwestern Colorado southward to northern Lower California, southern Arizona, and southern New Mexico. It spends the winter in Mexico. As a summer resident it is common and sometimes abundant in western Washington, even at lower elevations where, Samuel F. Rathbun tells me, it "prefers a locality somewhat open, with a second growth of young conifers; this may occur in the rather heavy forest, if such condition exists there, or along the edge of the timber; the species is partial to this character of growth." In southern Oregon, according to C. W. Bowles (1902), it seems to combine the habitat requirements of the eastern black-throated green and the prairie warbler. Like the former, it seeks tall trees, preferably conifers, well scattered and interspersed with bushes, since it nests in both. Like the prairie warbler, it chooses high dry places with dry ground underneath for its nest. Farther south, the black-throated gray warbler seems to prefer growths of hardwood and underbrush for its summer haunts--oaks, scrub oak, pinyon, juniper, manzanita, and the like. Dr. Walter K. Fisher wrote to Dr. Chapman (1907) that, in California, "it lives in chaparral such as deer brush, wild lilac of various species, scrub oak, and sometimes, particularly in the humid coast districts, among evergreens. It is fond of the neighborhood of clearings where it works constantly and carefully among low growth." Dr. Grinnell (1908) says that in the San Bernardino Mountains, "this warbler appeared to be be confined exclusively to the golden oak belt during the breeding season." Referring to the Great Basin region, Dr. Linsdale (1938) writes: "The black-throated gray warbler was one of the few species adapted to occupy the piñon belt on the Toyabe Mountains. Not only did this bird tolerate conditions on dry slopes, but it was practically limited to them. The pairs were scattered far apart, but because this type of habitat takes up so much of the total area, this warbler must rank high among all the summer resident birds on the basis of numbers."