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

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      The species of this genus are cosmopolitan, the greater number, however, being found in tropical regions. All the American species differ from S. zorca of Europe in having the fourth and fifth quills longest, instead of the second, and in having three to four, instead of only two, of the outer quills with the inner web sinuated, as well as in having the quills shorter, broader, and more bowed, and their under surface more concave. They may, perhaps, be distinguished as a separate subgenus (Megascops, Kaup). Of the American species all but S. asio (including its several races) have the toes perfectly naked to their very bases.

      Common Characters. Plumage brown, gray, or rufous, and whitish, finely mottled above; lower parts transversely barred, and with dark shaft-streaks. Outer webs of lower scapulars light-colored (white or ochraceous) and without markings. Tail crossed by rather obscure mottled light and dark bars of nearly equal width. Outer webs of primaries with nearly equal bands of whitish and dusky.

      Sp. Char. Adult. Ground-color above brownish-cinereous, palest on the head, purest ashy on the wings, minutely mottled with fine zigzag transverse bars of black, each feather with a medial ragged stripe of the same along the shaft. Inner webs of ear-tufts, outer webs of scapulars, and oval spots occupying most of the outer webs of the two or three lower feathers of the middle and secondary wing-coverts, white, forming (except on the first) conspicuous spots, those of the scapulars bordered with black. Secondaries crossed with about seven regular paler bands, each enclosing a more irregular dusky one; the ground-color, however, is so mottled with grayish, and the pale bands with dusky, that they are by no means sharply defined or conspicuous, though they are very regular; alula and primary coverts more sharply barred with cream-colored spots, those on the former nearly white; primaries with broad quadrate spots of creamy-white on outer webs, these forming from seven (♂) to eight (♀) transverse bands, the last of which is not terminal. Tail more irregularly mottled than the wings, and crossed by seven (♂) to eight (♀) narrow, obsolete, but continuous, pale bands.

      Eyebrows white, the feathers bordered with dusky (most broadly so in ♂); cheeks, ear-coverts, and lower throat dull white, with transverse bars of blackish (most numerous in the ♂); chin immaculate; upper eyelid dark brown; facial circle black; neck and jugulum like the cheeks, but more strongly barred, and with blackish along the shaft. Ground-color of the lower parts white, each feather with a medial stripe of black, this throwing off distinct bars to the edge of the feather; the medial black is largest on sides of the breast, where it expands into very large conspicuous spots, having a slight rusty exterior suffusion; the abdomen medially, the anal region, and the lower tail-coverts, are almost unvaried white. Tibiæ and tarsi in the male dull white, much barred transversely with blackish; in the female, pale ochraceous, more sparsely barred with dark brownish. Lining of the wing creamy-white, varied only along the edge; light bars on under surface of primaries very obsolete.

      ♂ (16,027, Fort Crook, North California; John Feilner). Wing, 6.70; tail, 3.80; culmen, .61; tarsus, 1.35; middle toe, .72; ear-tufts, 1.00; wing-formula, 3=4, 5–2, 6, 1=9. “Length, 9.50; extent, 23.75.”

      ♀ (18,299, Hellgate, Montana; Jno. Pearsall). Wing, 7.80; tail, 4.10; culmen, .70; tarsus, 1.70; middle toe, .80; ear-tufts, 1.00.

      Young ♂ (No. 29,738, Wood’s Hole, Mass., July 25, 1863; S. F. Baird. “Parent gray”). Secondaries, primaries, and tail, as in the adult, gray plumage; but the latter more mottled, the bands confused. Rest of the plumage everywhere grayish-white, СКАЧАТЬ