A History of North American Birds, Land Birds. Volume 3. Robert Ridgway
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Название: A History of North American Birds, Land Birds. Volume 3
Автор: Robert Ridgway
Издательство: Public Domain
Жанр: Биология
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B. Scapular process of the coracoid not produced forward so as to meet the clavicle (Huxley). Nasal bones incompletely ossified, the nostrils being very large, and without bony rim or tubercle. Inferior surface of the supramaxillary bone without a median ridge. Superciliary process of the lachrymal variable. (Accipitrinæ.)
a. Superciliary process of the lachrymal composed of a single, excessively abbreviated piece;44 posterior margin of the sternum with a pair of indentations, and without foramina. (Pandion and Nauclerus.)
b. Superciliary process of the lachrymal double, or composed of two pieces, joined by a cartilaginous “hinge,” and reaching nearly across the orbit. Posterior margin of the sternum without indentations, and usually with a pair of foramina. (All except Pandion and Nauclerus.)
† Septum of the orbits and nostrils incompletely ossified (the former always and the latter usually) and with foramina; posterior margin of the sternum most produced backwards laterally, and incompletely ossified, there being usually a pair of foramina. Intestinal canal short, broad, with the duodenum simple, forming a single loop (McGillvray). A well-developed “web” between the outer and middle toes. (All but Haliætus.)
†† Septum of the orbits and nostrils completely ossified, and without any trace of foramina; posterior margin of the sternum produced medially into a convex lobe, and without any trace of foramina. Intestinal canal extremely elongated, attenuated, with the duodenum arranged in several convolutions (McGillvray). No trace of a web between outer and middle toes. (Haliætus.)
Subfamily FALCONINÆ
Genus FALCO, Auct
Gen. Char. Bill strong, its breadth at the base equalling or exceeding its height; upper outline of cere on a level with, or rather lower than, the base of the culmen; gonys much arched, the chord of the arch equalling about half that of the culmen. Near the tip of the upper mandible is a prominent tooth on the commissure, and near the end of the lower mandible, which is truncated, is a deep notch corresponding; the end of the upper mandible is compressed, giving the situation of the tooth an inflated appearance when viewed from above. Nostrils circular, with a conspicuous central tubercle. Orbital region bare; projecting superciliary shield conspicuous, arched, but not very prominent. Tail shorter than wing, the feathers hard and stiff. Primaries very strong, elongated, tapering rapidly toward their points; only the first or first and second with their inner webs emarginated, the cutting being angular, and near the end of the quill. Tarsus never with a single series of transverse scutellæ either in front or behind; middle toe very long.
13077, ♀. ½
One primary only with inner web emarginated; first to second longest; first longer than fourth.
Tarsus longer than middle toe, and feathered far below the knee; first quill shorter than third. Coloration of the sexes alike; old and young slightly different in pattern and tints. Size large … Hierofalco.
Tarsus not longer than middle toe, and scarcely feathered below the knee; first quill equal to or longer than the third. Coloration of the sexes alike; old and young very different in pattern and tints. Size, very small to large … Falco.
Two primaries with inner webs emarginated; second to third longest; first shorter than fourth.
Basal joint of toes without transverse scutellæ; tarsus about equal to middle toe.
Coloration of the sexes in adult plumage very different in tints; in the young alike, the young ♂ resembling the adult ♀. Size small … Æsalon.
Basal joint of toes with transverse scutellæ; tarsus longer than middle toe.
Coloration of the sexes very different, in pattern and tints, at all ages; old and young alike. Scutellæ of the toes and tarsus interrupted at the digito-tarsal joint; tarsus much longer than middle toe. Bill small, the cere on top less than one fourth the culmen. Size small … Tinnunculus.
Coloration of the sexes alike at all ages; old and young slightly different in pattern and tints. Scutellæ of tarsus and toes uninterrupted from “knees” to claws; tarsus but little longer than middle toe. Bill large, the cere on top about one third the culmen. Size medium; form very slender … Rhynchofalco.
Hierofalco, Cuvier, 1817. (Type, Falco gyrfalco, Linn.)
Jerafalco, Boie, 1822; Kaup, 1851. (Same type.)
Gennaia, Kaup, 1847. (Type, Falco jugger, Gray.)
1. F. gyrfalco. Wing, 13.00–17.00; tail, 8.50–11.50; culmen, .85–1.05; tarsus, 2.10–3.00; middle toe, 1.80–2.25.45 Ground-color varying from entirely pure white to wholly dusky, but generally bluish (in adult) or grayish-brown (in young) above, and white beneath. Adult. All the markings transverse.46 No lighter nuchal band. Young. Markings of the lower surface longitudinal, the upper parts without transverse bars (except on the tail47).
a. Lower parts with white predominating, or wholly white.
Lower tail-coverts never with markings. No tinge of blue anywhere on the plumage, the ground-color of which is entirely pure white at all ages.
1. Adult. Upper parts, excepting head and neck, with transverse crescentic bars of dark plumbeous; lower parts immaculate, or else without well-defined markings. Young. Upper parts with longitudinal stripes of dark plumbeous; lower parts usually conspicuously striped. Hab. Greenland (in the breeding-season); in winter, occasionally wandering into the northern portions of Europe and North America … var. candicans.
Lower tail-coverts always with markings. A tinge of ashy-blue more or less prevalent above. Young dusky above.
Head and neck above abruptly lighter than the back. Young plain grayish-brown above, with conspicuous whitish borders to the feathers.
2. Adult. Upper parts white, passing into bluish posteriorly; everywhere (except on head and neck) with sharply defined, transverse (not crescentic, but continuous) bars of dark plumbeous. Abdomen and flanks with transverse spots of the same. Young without irregular light mottling to the plumage above, and with broad longitudinal stripes beneath. Hab. Iceland and Southern Greenland, in the breeding-season; in winter, south into Northeastern United States, and Northern Europe … var. islandicus.
Head and neck above abruptly darker than the back. Young (of var. sacer) variegated grayish-brown above, without light borders to the feathers.
3. Adult. Top of the head streaked with whitish; back with sharply defined, continuous, narrow transverse bars, of creamy-white. Hab. Interior regions of Continental Arctic America (Slave Lake, Yukon, and McKenzie River district) … var. sacer.
4. СКАЧАТЬ
Embracing besides the
As in the Polyborine forms of the
Extremes of sixty specimens.
Sometimes there are more or less distinct linear streaks on the head and neck, or on the pectoral region.
Sometimes the irregular markings above have a transverse tendency.