A History of North American Birds, Land Birds. Volume 2. Robert Ridgway

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      Sp. Char. Similar to P. arcticus in amount of white on the wings and scapulars, though this frequently edged with black, but without basal white on outer web of primaries. Outer edge of outer web of external tail-feather white, sometimes confluent with that at tip of tail. Concealed white spots on feathers of side of neck. Claws enormously large, the hinder longer than its digit; the hind toe and claw reaching to the middle of the middle claw, which, with its toe, is as long as or longer than the tarsus. Inner lateral claw reaching nearly to the middle of middle claw. Length, 7.60; wing, 3.25; hind toe and claw, .90. Female with the deep black replaced by dusky slaty-olive.

      Hab. Southern coast of California and across through valleys of Gila and Rio Grande; north through the Great Basin across from Fort Crook, California, to Fort Bridger, Wyoming.

      This form constitutes so strongly marked a variety as to be worthy of particular description. The general appearance is that of P. arcticus, which it resembles in the amount of white spotting on the wings. This, however, does not usually involve the whole outer web at the end, but, as in oregonus, has a narrow border of black continued around the white terminally and sometimes externally. There is not quite so much of a terminal white blotch on the outer tail-feather, this being but little over an inch in length, and the outer web of the same feather is never entirely white, though always with an external white border, which sometimes is confluent with the terminal spot, but usually leaves a brown streak near the end never seen in arcticus, which also has the whole outer web white except at the base. From oregonus the species differs in the much greater amount of white on the wings and the less rounded character of the spots. Oregonus, too, has the whole outer web of external tail-feather black, and the terminal white spot of the inner web less than an inch in length. We have never seen in oregonus any concealed white spotting on the sides of the head.

      The greatest difference between this race and the two others lies in the stout tarsi and enormously large claws, as described, both the lateral extending greatly beyond the base of the middle one, the hinder toe and claw nearly as long as the tarsus. The only North American passerine birds having any approach to this length of claw are those of the genus Passerella.

      This great development of the claws is especially apparent in specimens from the Southern Sierra Nevada, the maximum being attained in the Fort Tejon examples; those from as far north as Carson City, Nev., however, are scarcely smaller. In most Rocky Mountain Pipilos, the claws are but little longer than in arcticus.

      In this race the female is not noticeably different from the male, being of a merely less intense black,—not brown,—and conspicuously different as in arcticus and oregonus; there is, however, some variation among individuals in this respect, but none are ever so light as the average in the other races.

      The young bird is dusky-brown above, with a slight rusty tinge, and obsolete streaks of blackish. White markings as in adult, but tinged with rusty. Throat and breast rusty-white, broadly streaked with dusky; sides only tinged with rufous.

      Habits. According to Mr. Ridgway’s observations, the P. megalonyx replaces in the Rocky Mountain region and in the greater portion of the Great Basin the P. arcticus of the Plains, from their eastern slope eastward to the Missouri River, and the P. oregonus of the Northern Sierra Nevada and Pacific coast. It is most nearly related to the latter. He became familiar with the habits of this species near Salt Lake City, having already made like observations of the oregonus at Carson. A short acquaintance with the former, after a long familiarity with the latter, enabled him to note a decided difference in the notes of the two birds, yet in their external appearance they were hardly distinguishable, and he was at first surprised to find the same bird apparently uttering entirely different notes, the call-note of P. megalonyx being very similar to that of the common Catbird. The song of this species, he adds, has considerable resemblance in style to that of the eastern P. erythrophthalmus, and though lacking its musical character, is yet far superior to that of P. oregonus. This bird is also much less shy than the western one, and is, in fact, quite as unsuspicious as the eastern bird.

      Nests, with eggs, were found on the ground, among the scrub-oaks of the hillsides, from about the 20th of May until the middle of June.

      This species has been obtained on the southern coast of California, and through to the valleys of the Gila and the Rio Grande. In California it was obtained near San Francisco by Mr. Cutts and Mr. Hepburn; at Santa Clara by Dr. Cooper; at Monterey by Dr. Canfield; in the Sacramento Valley by Dr. Heermann; at San Diego by Dr. Hammond; at Fort Tejon by Mr. Xantus; at Saltillo, Mexico, by Lieutenant Couch; in New Mexico by Captain Pope; and at Fort Thorn by Dr. Henry.

      Lieutenant Couch describes it as a shy, quiet bird, and as found in woody places.

      Dr. Kennerly met with this bird at Pueblo Creek, New Mexico, January 22, 1854. It first attracted his attention early in the month of January, in the Aztec Mountains, along Pueblo Creek. There it was often met with, but generally singly. It inhabited the thickest bushes, and its motions were so constant and rapid, as it hopped from twig to twig, that they found it difficult to procure specimens. Its flight was rapid, and near the ground.

      Dr. Cooper speaks of this species as a common and resident bird in all the lower districts of California, and to quite a considerable distance among the mountains. It was also found on the islands of Catalina and San Clemente, distant sixteen miles from the mainland. Though found in New Mexico, Dr. Cooper has met with none in the barren districts between the Coast Range and the Colorado, nor in the valley of the latter.

      Their favorite residence is said to be in thickets and in oak groves, where they live mostly on the ground, scratching among the dead leaves in the concealment of the underbrush, and very rarely venturing far from such shelter. They never fly more than a few yards at a time, and only a few feet above the ground. In villages, where they are not molested, they soon become more familiar, take up their abodes in gardens, and build their nests in the vicinity of houses.

      Dr. Cooper gives them credit for little musical power. Their song is said to be only a feeble monotonous trill, from the top of some low bush. When alarmed, they have a note something like the mew of a cat. On this account they are popularly known as Catbirds. He adds that the nest is made on the ground, under a thicket, and that it is constructed of dry leaves, stalks, and grass, mingled with fine roots. The eggs, four or five in number, are greenish-white, minutely speckled with reddish-brown, and measure one inch by .70.

      Dr. Coues found this species a very abundant and resident species in Arizona. It was rather more numerous in the spring and in the fall than at other times. He found it shy and retiring, and inhabiting the thickest brush. Its call-note is said to be almost exactly like that of our eastern Catbird. He describes its song as a rather harsh and monotonous repetition of four or six syllables, something like that of the Euspiza americana. He found females with mature eggs in their ovaries as early as May 5.

      A nest of this species, collected by Mr. Ridgway near Salt Lake City, May 26, was built on the ground, among scrub-oak brush. It is a very slight structure, composed almost entirely of coarse dry stems of grass, with a few bits of coarse inner bark, and with a base СКАЧАТЬ