CERCHNEIS. Boie Isis, p. 976. (1826.)—POECILORNIS. Kaup Class. der Savg. und Vog, p. 108. (1844.) Size small, tarsus and toes lengthened, slender. Colors generally more or less rufous and white. In all other respects similar to typical _Falco_. This genus comprises about twelve very handsome species of small size, inhabiting various countries. 1. Tinnunculus sparverius. (Linn.) The Sparrow Hawk. Falco sparverius. Linn. Syst. Nat. I. p. 128. (1766.) Falco dominicensis. Gm. Syst. Nat. I. p. 285. (1788.) Falco gracilis, cinnamominus and isabellinus. Sw. Cab. Cy. p. 281. (1838.) Vieill. Ois. d’Am. Sept. pl. 12, 13. Cat. Car. pl. 5. Buff. Pl. Enl. 465. Wilson Am. Orn. II. pl. 16, fig. 1, and IV. pl. 32, fig. 2. Faun. Bor. Am. Birds, pl. 24. Aud. B. of Am. pl. 42. Oct. ed. I. pl. 22. Nat. Hist. N. Y. Birds, pl. 7, fig. 16. Small, wings moderate, tail rounded. Adult Male. Frontal band, space including the eyes and throat, white; spot on the neck behind, two others on each side of the neck, and line running downwards from before the eye, black. Head above, and wing coverts, bluish cinereous, the latter usually spotted with black. Spot on the top of the head, the neck behind, back, rump, and generally the tail above, light rufous or cinnamon red. Under parts generally a pale shade of the same color, frequently nearly white, but sometimes nearly as dark as the back, and always with more or less numerous circular, or oblong spots of black. Quills brownish black, with white bars on their inner webs. Tail tipped with white, sometimes tinged with rufous, and with a broad subterminal band of black, frequently with several of the outer feathers, white tinged with ashy, and barred with black. Bill blue, legs and feet yellow. Back generally with more or less numerous transverse stripes of black. Rufous spot on head, much varying in size, and sometimes wanting. Female. Upper parts as above, and wing coverts, and tail rust red, with numerous transverse bands of brownish black, under parts with numerous longitudinal stripes, and on the sides and flanks, with transverse bands of the same color, external feathers of the tail palest, broad subterminal band on the tail, obscure or wanting. Young Male. Wing-coverts, dark bluish cinereous with large circular spots, and with bands of brownish black, all the rufous parts with broad bands of the same color, under parts with large circular spots, and wide traverse bands of black on the sides and flanks. Dimensions. Total length, 11 to 12 inches, wing 7 to 7½, tail 5 to 5½ inches. Sexes nearly alike in size. Hab. The entire continent of America. California, (Mr. Bell.) Mexico, (Mr. Pease.) Cuba, (M. de Sagra.) Bermuda, (Sir W. Jardine.) Chili, (Lieut. Gilliss.) Patagonia, (Ex. Exp. Vincennes.) Spec. in Mus. Acad. Philada.