A History of North American Birds, Land Birds. Volume 1. Robert Ridgway

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СКАЧАТЬ to bear the weight of the parent bird. This, however, all my observations attest to be not the fact. The nest is, on the contrary, very elaborately and carefully constructed; large for the size of the bird, remarkably deep, and with thick, warm walls composed of soft and downy materials, but abundantly strong for its builder, who is one of our smallest birds both in size and in weight. Like the nests of the Wood Pewee and the Humming-Bird, they are models of architectural beauty and ingenious design. With walls made of a soft felted material, they are deep and purse-like. They are not pensile, but are woven to small upright twigs, usually near the tree-top, and sway with each breeze, but the depth of the cavity and its small diameter prevent the eggs from rolling out. Externally the nest is covered with a beautiful periphery of gray lichens, assimilating it to the bark of the deciduous trees in which it is constructed.

      Occasionally these nests have been found at the height of ten feet from the ground, but they are more frequently built at a much greater elevation, even to the height of fifty feet or more. They are made in the shape of a truncated cone, three inches in diameter at the base and but two at the top, and three and a half inches in height. The diameter of the opening is an inch and a half. In Northern Georgia they nest about the middle of May, and are so abundant that the late Dr. Gerhardt would often find not less than five in a single day, and very rarely were any of them less than sixty feet from the ground. Dr. Gerhardt, who was an accurate and careful observer, speaks of these as the best built nests he had met with in this country, both in regard to strength and its ingeniously contrived aperture, so narrowed at the top that it is impossible for the eggs to roll out even in the severest wind. They have two broods in the season in the Southern States, one in April and again in July.

      This Flycatcher lays usually five eggs. These are of a short oval form, somewhat pointed at one end and rounded at the other, and measure .56 of an inch in length by .44 in breadth. Their ground-color is a greenish-white, marked and dotted with small blotches and spots of varying and blending shades of reddish-brown, lilac, and slate.

Polioptila plumbea, BairdLEAD-COLORED GNATCATCHER; ARIZONA GNATCATCHER

      Polioptila plumbea, Baird, Pr. A. N. Sc. VII, June, 1854, 118.—Ib. Birds N. Am. 1858, 382, pl. xxxiii, fig. 1; Review, 74.—Cooper, Birds Cal. 1, 37.

      Sp. Char. Above bluish-gray; the forehead uniform with the crown. Eyelids white. A pale grayish-white line over the eye, above which is another of black, much concealed by the feathers, and which does not reach to the bill. Lower parts dull white, tinged with bluish on the sides and with brownish behind. Tail-feathers black; the first and second edged and tipped with white, involving the entire outer web of the first, and most of that of the second; the third with only a very faint edging of the same. Female duller, without the black superciliary line. Length, 4.40; wing, 1.80; tail, 2.30 (7,189).

      Hab. Arizona.

      This species differs from P. cærulea, in having the ash above less bluish, especially on the forehead; the black superciliary streak is only a horizontal bar, not reaching the bill, whereas in cærulea it not only reaches the bill, but also extends across the forehead; the light superciliary stripe is more distinct. The tail is entirely different, the lateral feathers being almost entirely black, instead of the reverse.

      From immature specimens of P. melanura it may be distinguished by larger size and purer white lower parts, and greater amount of white on outer webs of lateral tail-feathers.

      Habits. But little is known in regard to the distribution or history of this species. It appears to be peculiar to Arizona and Mexico. There is no good reason to suppose that it differs materially in any of its habits from the other species of this genus. Dr. Cooper, who observed this species at Fort Mojave, states that it is a winter resident of that region in small numbers; and, so far as he observed, is undistinguishable either in habit or general appearance from either of the other species which at that season are also found there. Its cry of alarm resembles that of the common wren.

Polioptila melanura, LawrBLACK-CAPPED GNATCATCHER

      Culicivora atricapilla, Lawrence, Ann. N. Y. Lyc. V, Sept. 1851, 124 (not of Swainson). Culicivora mexicana, Cassin, Illust. I, 1854, 164, pl. xxvii (not of Bon.). Polioptila melanura, Lawrence, Ann. N. Y. Lyc. VI, Dec. 1856, 168.—Baird, Birds N. Am. 1858, 382; Review, 68.—Heermann, P. R. R. R. vol. X (Williamson), 1859, 39.—Cooper, Birds Cal. 1, 37.

      Sp. Char. Above plumbeous-blue. Whole crown, to bill and eyes, with tail, lustrous blue-black. Beneath pale bluish-gray, almost white on chin and anal region; the flanks and crissum tinged with brown. Edge of eyelids, and margin and tip of outer web of first and second lateral tail-feathers, white. Female and young without the black of the crown. Length, 4.15; wing, 1.85; tail, 2.10.

      Hab. San Diego to Fort Yuma and Cape St. Lucas. Arizona, Coues.

      Specimens of this species from Cape St. Lucas differ from those of San Diego described in the P. R. R. Report (7,191) in having the whole of the outer web of the outer tail-feather white, and in a rather larger white tip. The colors beneath are a little less ashy, though not of a pure white. The ash of the back is rather lighter and purer. The lores are rather lighter. The first primary is a little larger and broader.

      It is possible that the restriction of the white of the outer web of the exterior tail-feather to the outer half only is an unusual circumstance, as both Mr. Cassin and Mr. Lawrence, in their descriptions, speak of the entire outer web being white,—the second feather being of the former character. Under these circumstances there will be little specific difference between the tails of P. melanura and plumbea. The female birds will then be separated by the light superciliary line and much shorter tarsi of P. plumbea,—the latter measuring .63 instead of nearly .70 of an inch.

      Habits. This species was first noticed as belonging to the North American fauna by Captain McCown, who obtained it near Ringgold Barracks in 1850. It has since been noticed at Fort Yuma and at San Diego, and obtained in greater abundance at Cape St. Lucas. It is also found in Mexico. Dr. Cooper says that it is common all winter both at San Diego and at Fort Mohave. It has been traced as far north as latitude 30° in the Sierra Nevada. Its song he describes as a harsh ditty of five parts, something like a wren’s song, with notes like those of a swallow, and also closely resembling the song of Vireo belli. Their scolding note is a faint mew, like that of a cat.

      The habits of this species appear to be not unlike those of the peculiar family to which it belongs. All its members are among our smallest birds, are almost exclusively inhabitants of woods, and resemble the Reguli in their restless activity in pursuit of the smallest insects on which they feed. This bird is described as particularly active, quick in its movements, searching with great activity for its food, and preferring low trees and bushes. At times it will dart about in the air in pursuit of small insects.

      Mr. John Xantus found these birds to be quite abundant at Cape St. Lucas, and obtained several of their nests. They were generally built among the interlacing tendrils of a wild vine (Antigonon leptopus), and so closely interwoven with the smaller branches as to be inseparable. The nests, like those of all this family, are structures of great beauty and delicacy. They have a height and an external diameter of about 2¼ inches. The cavity is 1½ inches wide at the rim, and fully two inches deep. This great proportionate depth of the nest seems to be characteristic of this genus. The external portion of this nest is composed of a composite blending of various vegetable materials, fine hempen fibres of plants, strips of delicate bark from smaller shrubs, silken fragments of cocoons and downy cotton-like substance, all very closely impacted and felted together, somewhat after the manner of the Humming-Bird. The whole is very softly and warmly lined with a beautifully interwoven and silky fabric composed of the soft down of various plants.

      The walls of the nest, though of the softest materials, are so thick and so firmly impacted as to make it a structure remarkably firm and secure against accidents.

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