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

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      Sp. Char. Adult male; spring. A frontal crescent, curving backward in a broad, sharply defined, superciliary stripe to the occiput; chin, throat and foreneck, and a crescent across middle of ear-coverts, whitish, either more or less tinged with yellow, or pure white. Lower parts, except laterally, white. A broad crescentic patch behind the frontal whitish crescent, running back on each side of the crown and terminating in an erectile tuft of narrow elongated feathers on each side of occiput, a patch covering the lores, nasal tufts, passing beneath the eye, and forming a broad “mustache” on the cheeks, with a convex outline behind and concave anteriorly, and a broad crescentic patch across the jugulum, deep black. A crescentic spot of grayish-drab across the ends of the auriculars. Posterior portion of the crown enclosed laterally between the “ear-tufts,” occiput, nape, lateral lower parts, lesser and middle wing-coverts, and upper tail-coverts, pinkish-brown; the sides and flanks with obsolete dusky streaks. Back, scapulars, rump, wings, and two middle tail-feathers, ashy-drab, the feathers darker centrally, forming rather conspicuous broad streaks on lower part of back; middle and secondary coverts, secondaries and primaries bordered terminally, quite conspicuously, with white. Tail (except the intermediæ) black; outer web of lateral feather almost entirely white, that of the next edged with the same.

      Adult female; spring. Similar, but markings rather less sharply defined; a tendency to streaking of nape and crown; these streaks often displacing the continuous black of the anterior portion of crown. The “ear-tufts” less developed.

      Winter adult. Similar to the spring dress, but the black areas obscured, more or less, by whitish borders to the feathers; the frontal whitish band less sharply defined. Breast with numerous more or less distinct deltoid specks of plumbeous, and the pinkish of the sides much tinged with the same. The dusky streaks above are broader and more conspicuous.

      Young. First plumage, entirely different from the adult. Above dusky, variegated with whitish dots, sprinkled over the whole surface; these specks terminal on each feather, and of a deltoid form, becoming more transverse and crescentic on the scapulars and rump; each feather of the wings broadly bordered with pale brownish, approaching white on the coverts. The blackish areas are but faintly indicated by a dusky suffusion, generally very indistinct, across the breast, and over the cheeks; and variegated with badly defined, more dusky spots; lower parts, including post-ocular stripe, dull white; sides spotted with dusky.

      The E. alpestris, as restricted, is represented in the collection by three perfect specimens, in the several stages of plumage described; while there is also a fine specimen from Astrachan, representing a white-throated race (“var. bei” on MS. label) of Central Asia. The series of American specimens is all that could possibly be desired, there being numerous examples from nearly the whole northern continent, from the Arctic regions to as far south as Bogota, and from coast to coast.

      The common Shore Lark of the northern parts of North America appears to be absolutely identical with the European bird, each of the specimens of the latter being easily matched from the American series. It therefore becomes necessary to reduce the name “cornuta” to a synonyme of alpestris, the former not affording characters to distinguish it as even a variety. To alpestris may also be referred the form known as “occidentalis, McCall,” those specimens from the interior regions which are destitute of any yellow tinge on the throat. Were this feature a constant one in specimens from the region which it characterizes, it would be, of course, right to retain the name in the form of alpestris var. occidentalis. As it is, however, quite a large percentage of the specimens from every locality where occidentalis is found have more or less yellow throats, but it is possible that this mixture of the two may be the result of irregular migrations, those yellow-throated individuals being stragglers from their breeding habitat,—more to the eastward and northward. In its white instead of straw-yellow throat, and more lilaceous than vinaceous upper parts, this form bears a close resemblance to a race of the deserts of Western (and Central?) Asia,—the “bei”26; the latter, however, has these features more exaggerated than in the one of the central plains of North America. Breeding throughout the table-lands of Mexico, and in the Western Province of the United States, north to about the 40th parallel, is a more strongly marked race, maintaining also more constancy in its peculiar features; this race is the E. chrysolæma, Wagl., of which name rufa, Aud., and minor, Giraud, are synonymes. This race, which we propose to call E. alpestris var. chrysolæma, differs from both the northern styles in smaller size and longer bill, and in coloration is the opposite extreme from occidentalis, having the vinaceous tints deeper and browner, instead of paler and less brown, than in cornuta (i. e. typical alpestris). The black markings are also more extended, in proportion to the other colors, reducing the white on the forehead to a very narrow band, instead of a broad spot equalling, or exceeding, the black in width. Specimens from Bogota—about the southern limit of the genus on this continent—are, perhaps, referrible to chrysolæma, or at least not very different from it, though described by Sclater as distinct, under the name peregrinus.27

      In fewer words, the variations, with the region, are about as follows. Starting with North America, north of the United States, we begin with a style absolutely undistinguishable from that of Europe; this, to which the name cornuta belongs, visits the Eastern States only in winter, but breeds over the prairie region of Wisconsin, Illinois, and westward. West of the Rocky Mountains, especially south of about 40°, specimens referrible to this style are most numerous in winter, and in a large series a great percentage of the specimens entirely lack any СКАЧАТЬ