A History of North American Birds, Land Birds. Volume 3. Robert Ridgway

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      A specimen from Nicaragua (No. 40,957, Chinandega) is like North American examples, but the reddish tinge beneath is scarcely discernible, and confined to the tibiæ, which are but faintly ochraceous; the markings beneath are broad and deep umber, the black shaft-streak distinct.

      In the adult female there is as little variation as in the male in plumage, the shade of brown above varying slightly, also the yellowish tinge beneath; the bars on the tail differ in continuity and tint in various specimens, although they are always five in number,—the first concealed by the coverts, the last terminal. In 19,382, Fort Simpson, British America, and 2,706, Yukon, R. Am. (probably very old birds), the light bars are continuous and pale dull ashy.

      The young vary about the same as adults. Nos. 19,381, Big Island, Great Slave Lake; 5,483, Petaluma, California; and 3,760, Racine, Wisconsin,—are young males moulting, scattered feathers appearing on the upper parts indicating the future blue plumage.

      Sp. Char. A miniature of F. peregrinus, var. pealei. Above, uniform fuliginous-black, the secondaries and tail-feathers very narrowly but sharply tipped with white, and the primaries passing into whitish on their terminal margin; nuchal region with concealed spotting of pale rusty or dingy whitish. Beneath, longitudinally striped with fuliginous-black, or dark sooty-brown, and pale ochraceous; the former predominating on the breast, the latter prevailing on the throat and anal region. Sides and flanks nearly uniform dusky, with roundish white spots on both webs; lower tail-coverts with a broad sagittate spot of dusky on each feather. Lining of the wing fuliginous-dusky, with sparse, small roundish spots of white. Inner webs of primaries plain dusky, without spots, or else with them only faintly indicated. Tail plain dusky-black, narrowly tipped with white, and without any bands, or else with them only faintly indicated.

      Male (No. 4,477, Shoalwater Bay, Washington Territory; J. G. Cooper). Wing, 7.35; tail, 5.25; culmen, .50; tarsus, 1.30; middle toe, 1.25.

      Female (No. 5,832, Fort Steilacoom, Washington Territory, September, 1856; Dr. George Suckley). Wing, 8.50; tail, 5.70; culmen, .55; tarsus, 1.62; middle toe, 1.35.

      Hab. Coast region of Northern California, Oregon, and Washington Territory (probably northward to Alaska). Puget Sound, Steilacoom, Yreka, California (Oct.), and Shoalwater Bay (National Museum).

      The plumage of this race is the chief point wherein it differs from the other forms of the species; and in its peculiarities we find just what should be expected from the Oregon region, merely representing as it does the melanistic condition so frequently observable in birds from the northwest coast.

      The upper parts are unicolored, being continuous blackish-plumbeous from head to tail. The tail is tipped with white, but the bars are very faintly indicated, being in No. 4,499 altogether wanting, while in 21,333 they can scarcely be discovered, and only four are indicated; in the others there is the usual number, but they are very obsolete. In No. 4,499, the most extreme example, the spots on the inner webs of the primaries are also wanting; the sides of the head are very thickly streaked, the black predominating, leaving the superciliary stripe ill-defined; the throat is streaked, and the other dark markings beneath are so exaggerated that they cover all portions, and give the prevailing color; the under tail-coverts have broad central cordate black spots.

      Another specimen from this region (4,476, Puget Sound) is similar, but the spots on primaries are conspicuous, as in examples of the typical style; indeed, except in the most extreme cases, these spots will always be found indicated, leading us to the unavoidable conclusion that the specimens in question represent merely the fuliginous condition of the common species; not the condition of melanism, but the peculiar darkened plumage characteristic of many birds of the northwest coast, the habitat of the present bird; it should then be considered as rather a geographical race, co-equal to the Falco gyrfalco, var. labradora, F. peregrinus, var. pealei, and other forms, and not confounded with the individual condition of melanism, as seen in certain species of Buteones.

      National Museum, 6.

      Second quill longest; first quill equal to, a little shorter than, or a little longer than, the fourth.

Var. richardsoni, RidgwayRICHARDSON’S MERLIN

      Falco æsalon, Rich. & Swains. F. B. A. II, pl. xxv, 1831.—Nutt. Man. Orn. II, 558.—Coues, P. A. N. S. Philad. 1866, p. 42 (in text). Falco (Hypotriorchis) richardsoni, Ridgway, P. A. N. S. Philad. Dec. 1870, 145. Falco richardsoni, Coues, Key, 1872, p. 214.

      Sp. Char. Adult male like the female and young? The known stages of plumage more like the adult female and young of var. lithofalco (F. æsalon, Auct.) than like var. columbarius.

      Adult male (Smithsonian, No. 5,171, mouth of the Vermilion River, near the Missouri, October 25, 1856; Lieutenant Warren, Dr. Hayden). Upper plumage dull earth-brown, each feather grayish-umber centrally, and with a conspicuous black shaft-line. Head above approaching ashy-white anteriorly, the black shaft-streaks being very conspicuous. Secondaries, primary coverts, and primaries margined terminally with dull white; the primary coverts with two transverse series of pale ochraceous СКАЧАТЬ