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The characters of this subfamily will be found on page 69.

Genus POLIOPTILA, Sclat

Polioptila, Sclater, Pr. Zoöl. Soc. 1855, 11. (Type, Motacilla cærulea.)

Polioptila cærulea.

10213

Char. Bill slender, attenuated, but depressed at the base; nearly as long as the head, distinctly notched at the tip, and provided with moderate rictal bristles. Nostrils rather elongated, not concealed, but anterior to the frontal feathers. Tarsi longer than the middle toe, distinctly scutellate; the toes small; the hinder one scarcely longer than the lateral; its claw scarcely longer than the middle. Outer lateral toe longer than the inner. First primary about one third the longest; second equal to the seventh. Tail a little longer than the wings, moderately graduated; the feathers rounded. Nest felted and covered with moss or lichens. Eggs greenish-white, spotted with purplish-brown.

The species all lead-color above; white beneath, and to a greater or less extent on the exterior of the tail, the rest of which is black. Very diminutive in size (but little over four inches long).

Synopsis of Species

Top of head plumbeous

Two outer tail-feathers entirely white. A narrow frontal line, extending back over the eye, black. Hab. North America … P. cærulea.

Outer tail-feather, with the whole of the outer web (only), white. No black on the forehead, but a stripe over the eye above one of whitish. Hab. Arizona … P. plumbea.

Top of head black

Edge only of outer web of outer tail-feather white. Entire top of head from the bill black. Hab. Rio Grande and Gila … P. melanura.

Species occur over the whole of America. One, P. lembeyi, is peculiar to Cuba, and a close ally of P. cærulea.

Polioptila cærulea, Sclat

BLUE-GRAY GNATCATCHER; EASTERN GNATCATCHER

Motacilla cærulea, Linn. Syst. Nat. I, 1766, 337 (based on Motacilla parva cærulea, Edw. tab. 302). Culicivora cærulea, Cab. Jour. 1855, 471 (Cuba).—Gundlach, Repert. 1865, 231. Polioptila cærulea, Sclater, P. Z. S. 1855, 11.—Baird, Birds N. Am. 1858, 380.—Ib. Rev. 74.—Dresser, Ibis, 1865, 231.—Cooper, Birds Cal. 1, 35. Motacilla cana, Gm. S. N. I, 1788, 973. ? Culicivora mexicana, Bon. Consp. 1850, 316 (not of Cassin), female. Polioptila mexicana, Sclater, P. Z. S. 1859, 363, 373.

Figures: Vieill. Ois. II, pl. lxxxviii.—Wilson, Am. Orn. II, pl. xviii, fig. 3.—Aud. Orn. Biog. I, pl. lxxxiv; Ib. Birds Am. I, pl. lxx.

Sp. Char. Above grayish-blue, gradually becoming bright blue on the crown. A narrow frontal band of black extending backwards over the eye. Under parts and lores bluish-white tinged with lead-color on the sides. First and second tail-feathers white except at the extreme base, which is black, the color extending obliquely forward on the inner web; third and fourth black, with white tip, very slight on the latter; fifth and sixth entirely black. Upper tail-coverts blackish-plumbeous. Quills edged externally with pale bluish-gray, which is much broader and nearly white on the tertials. Female without any black on the head. Length, 4.30; wing, 2.15; tail, 2.25. (Skin.)

Hab. Middle region of United States, from Atlantic to Pacific, and south to Guatemala; Cape St. Lucas. Cuba, Gundlach and Bryant. Bahamas, Bryant.

Habits. The Blue-gray Flycatcher is a common species from the Atlantic to the Pacific coast, although not met with in the New England States. It is less abundant on the coast than at a distance from it, and has a more northern range in the interior, being met with in Northern Ohio, Michigan, and the British Provinces. Specimens occur in the Smithsonian Institution collection from New York to Mexico and Guatemala, and from Washington Territory to California.

They appear in Pennsylvania early in May, and remain there until the last of September. They are observed in Florida and Georgia early in March, but are not known to winter in that latitude. All the specimens in the Smithsonian collection were obtained between April and October, except one from Southern California, which was taken in December.

Polioptila cærulea.

Near Washington, Dr. Coues states the Blue-gray Gnatcatcher to be a summer resident, arriving during the first week of April, and remaining until the latter part of September, during which time they are very abundant. They are said to breed in high open woods, and, on their first arrival, to frequent tall trees on the sides of streams and in orchards.

In California and Arizona this species occurs, but is, to some extent, replaced by a smaller species, peculiarly western, P. melanura. There they seem to keep more about low bushes, hunting minute insects in small companies or in pairs, and their habits are hardly distinguishable from those of Warblers in most respects.

The food of this species is chiefly small winged insects and their larvæ. It is an expert insect-catcher, taking its prey on the wing with great celerity. All its movements are very rapid, the bird seeming to be constantly in motion as if ever in quest of insects, moving from one part of the tree to the other, but generally preferring the upper branches.

Nuttall and Audubon, copying Wilson, speak of the nest of this Gnatcatcher as a very frail receptacle for its eggs, and as hardly strong enough 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, Baird

LEAD-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, Lawr

BLACK-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.

The eggs, four in number, measure .55 of an inch in length by .45 in breadth. They are of an oblong-oval shape, their ground-color is a pale greenish-white sprinkled over the entire surface with fine dottings of purple, reddish-brown, and black.