Throat, sides of the neck and upper part of the breast white, with a tinge of buff without spots, other under parts same color, with a deeper shade, and with cordate or rounded spots of black on the lower breast and abdomen, and transverse bars of the same black on the sides, under tail-coverts and tibiæ. Quills, brownish black, with transverse bars of yellowish white on their inner webs. Tail, brownish black, with transverse bars of cinereous, very pale and nearly white on their inner webs, and narrowly tipped with white. Cheeks with a patch of black most narrow and clearly defined in the adult bird, and separated from the color of the back of the head by a white space; back of the neck, mixed with yellowish feathers, forming an irregular collar. Bill, light bluish horn color, paler at the base; legs and feet fine yellow. Sexes alike. Younger. Entire plumage above, brownish black; nearly uniform on all parts, and with little or no appearance of the bars which are seen in the adult. Tail, uniform dark brown, with spots or irregular transverse stripes of reddish white frequently only on the inner webs. Frontal spot of white obscure, large space on the cheek, black not separated posteriorly from the same color of the head above. Under parts, white and yellowish white, every feather, except on the throat, with a wide _longitudinal_ stripe of dark brown; the latter color prevailing on the sides and abdomen. Throat, white, nearly every feather with a very narrow central line of black. Tarsi and feet, bluish lead color. Dimensions. Female, total length 19 to 20 inches; wing, 14½ to 15; tail, 7½ to 8 inches. Male and young smaller. Hab. The entire eastern portion of North America, and perhaps western; Greenland? Oregon? (U. S. Ex. Exp.) Jamaica, (Mr. Gosse.) Cuba, (Mr. Lembeye.) Bermuda, (Sir W. Jardine.) Spec. in Mus. Acad. Philada. Obs. In the adult of this species, there is a white frontal band as in the adult of the European _F. peregrinus_. It is very similar in color and general characters to that species, but is larger, and the young differ. Audubon’s figures represent the dark-colored plumage described above as that of young or immature birds. Wilson’s figure is that of a more adult specimen, with the frontal band partially produced; but the bird in completely mature plumage, has never been figured. This bird frequently appears in the United States, generally on the sea-coast in the autumn and winter, at which seasons, also, according to Mr. Lembeye, it visits the island of Cuba. It flies with extraordinary vigor and rapidity, and is remarkable for its bold and destructive habits. 2. Falco nigriceps. Cassin,[3] _new species_. The Western Peregrine Falcon.