out to move off a little farther, still screeching louder than before, and this piece of deception it will repeat time after time, improving a little in its powers of locomotion as it gets you farther from the nest, until it judges it is far enough,—that you have lost the place in the unmarked sea of grass,—when it seems to fly as well as ever; it circles round once or twice, going still farther off, and settles silently down in the deep grass. This last performance is to induce the belief that it has returned to the nest. But if you refuse to be led astray by these manœuvres, and remain about its nest, it will make a good fight. One came very near knocking off my hat one day when I did not know I was intruding on its premises.”
The Buteo bairdi of Hoy is now ascertained to be only an immature form. It was first met with in Wisconsin, and since then has been taken in various western localities.
A pair of these birds was found by Mr. Ricksecker, breeding in this plumage, in Utah. The nest was built in a young aspen-tree. The egg is marked with larger and more deeply marked blotches than usual, and is nearly of an exact oval shape, measuring 2.30 inches in length by 1.75 in breadth. The ground-color is white, with a slight tinge of rufous, over which are diffused, over the whole surface, fine markings of a reddish, rust-tinged brown. Besides these the larger end, and some other portions of the surface, are boldly dashed with large blotches of the same color, but of a deeper shade.
A black Buzzard, originally described as Buteo insignatus, is now known to be only an individual melanistic condition of the species. It was first met with in the vicinity of Montreal, and the specimen belonging to the Natural History Society of that city was described as new by Mr. John Cassin. A similar specimen was taken by Mr. Macfarlane at Fort Anderson, where it was breeding. It was met with rather abundantly by Dr. Heermann on the San Joaquin River, in California, and seen along his route for a considerable distance. He described it as sluggish in its habits, perching for hours in a quiescent state on some tall tree, and permitting the hunter to approach without showing any signs of fear.
Buteo swainsoni, var. oxypterus (young).
Dr. Cooper found this bird pretty common in the vicinity of San Diego, in March, 1862, when they were apparently migrating northward. In their habits they appeared to resemble the larger varieties of Buzzards. Mr. Salvin obtained a single specimen of a Hawk at Duenas, which is referred by Mr. Gurney to this variety (Ibis, I, 216).
The variety oxypterus, of this species, was first described from an immature specimen obtained at Fort Fillmore, New Mexico. It ranges southward throughout tropical America to Buenos Ayres.