A History of North American Birds, Land Birds. Volume 2. Robert Ridgway

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      This Grosbeak builds in low trees on the edge of woods, frequently in small groves on the banks of streams. Their nests are coarsely built, with a base composed of waste stubble, fragments of leaves, and stems of plants. These are intermingled with and strengthened by twigs and coarser stems. They have a diameter of eight inches, and a height of three and a half. The upper portion of the nest is usually composed of dry usnea mosses, mingled with a few twigs, and lined with finer twigs. Its cavity is three inches in diameter and one in depth, being quite shallow for so large a nest.

      The eggs bear some resemblance to those of the Pyrangæ, but are usually much larger, though they vary greatly in size. Their ground-color is usually a light but well-marked shade of verdigris-green, varying occasionally to a greenish-white, and are marked, more or less, over their entire surface, with blotches of reddish-brown. They vary in length from 1.05 to .90 of an inch, and from .78 to .60.

      During incubation, and in the presence of its mate, this Grosbeak is a persistent and enthusiastic singer, and, at times, carries his love of song so far as to betray his nest. This is more especially so when he relieves his mate, takes her place on the nest, and then, apparently oblivious of the danger of lifting up his voice in song when upon so responsible a duty, attracts, by his melody, the oölogist to his treasures.

      Dr. Hoy, of Racine, supplies some interesting information in regard to the habits and nesting of this species. On the 15th of June, within six miles of that city, he found seven nests, all within a space of not over five acres, and he was assured that each year they resort to the same locality and nest thus socially. Six of these nests were in thorn-trees, all were within six to ten feet from the ground, and all were in the central portion of the top. Three of the four parent birds sitting on the nests were males, and this he was told was usually the case. When a nest was disturbed, all the neighboring Grosbeaks gathered around and appeared equally interested. Both nest and eggs so closely resemble those of the Tanagers that it is difficult to distinguish them. Their position is, however, usually different, the Grosbeaks generally nesting in the central portion of a small tree, the Tanagers’ being placed on a horizontal limb.

      Sp. Char. Male. Head above and on the sides, with chin, back, wings, and tail, black. A well-marked collar on the hind neck all round (and in var. capitalis a more or less distinct median stripe on crown, and one behind the eye), edges of interscapular feathers, rump, and under parts generally pale brownish-orange, almost light cinnamon. Middle of belly, axillaries, and under wing-coverts, yellow. Belly just anterior to the anus, under tail-coverts, a large blotch at the end of the inner webs of first and second tail-feathers, a band across the middle and greater wing-coverts, some spots on the ends of the tertiaries, the basal portions of all the quills, and the outer three primaries near the tips, white. Length nearly 8 inches; wing, 4.25; tail, 3.50.

      Female has the chin, sides of throat, and superciliary stripe white; the black markings replaced by olivaceous-brown; the cinnamon markings paler, and almost white; the white of wings more restricted; that of tail wanting. Usually there are few or no streaks beneath as in ludovicianus (faint ones on flanks); in young males, however, they are more appreciable. The lemon or gamboge yellow axillars and under coverts in all ages and stages separate this species from H. ludovicianus, the female and young of which have those regions of a saffron or fulvous yellow.

      Hab. High Central Plains from Yellowstone to the Pacific. Table-lands of Mexico. Xalapa (Scl. 1859, 365); Orizaba (Scl. 1857, 213); Vera Cruz, Alpine and plateau, breeding (Sum. M. B. S. I, 551).

      This bird, in its range of habitat, appears to be represented by two varieties, which, however, run into each other, so that it is often difficult to determine to which variety specimens from intermediate regions should be referred.

      Taking the series from Eastern Mexico (Orizaba and Mirador) and northward along the Rocky Mountains of the United States, we find the black of the head continuous, sharply defined by a gently curved outline behind, and without a trace of either the vertex or post-ocular stripes. This is the true melanocephalus, as restricted, and may be regarded as the Rocky Mountain form. The most western specimen is 11,241, from Fort Bridger; the most northern (19,355), from Stinking River, Northern Wyoming. All specimens from the Pacific coast eastward to the western base of the Rocky Mountains, including Cape St. Lucas and Western Mexico south to Colima, differ from the Rocky Mountain series in having the posterior outline of the black hood ragged, and irregularly indented by the rufous of the nape, which always extends in a quite broad stripe toward the eye, along the side of the occiput, and quite frequently forms a conspicuous median vertex stripe, though the latter feature is sometimes not distinct. These differences are observable only in the males, and, although apparently slight, are yet sufficiently constant to justify distinguishing them as races. The Rocky Mountain form being the true melanocephalus, the name capitalis is proposed for the western one.

      Habits. This bird occurs from the high Central Plains to the Pacific, and from the northern portions of Washington Territory to the table-lands of Mexico. Mr. Ridgway found this species abundant, during the summer months, in all the fertile wooded districts along the entire route of the survey. At Sacramento it was common in the willow copses, and was observed in the greatest numbers, in May, in the rich valley of the Truckee, in company with Bullock’s СКАЧАТЬ