Smaller than the preceding; wing with the third quill slightly longest; tail ample, rounded; neck with an uninterrupted collar of white before and fulvous behind; head above ashy-gray, with a longitudinal stripe of brownish-black; back and rump dark brown, with minute points and irregular lines of cinereous; under-parts mottled with pale reddish-white and brownish-black, the latter most conspicuous on the breast, the former on the abdomen and under tail-coverts; four middle feathers of the tail mottled with gray and brownish-black, the latter forming irregular bands; external feathers of the tail brownish-black, widely tipped with silky white, and with traces of rufous bars towards the base; quills brownish-black, with interrupted bars of rufous; exposed ends of primaries same as the back. Female rather smaller than the male, with the white collar on the neck tinged with fulvous, which is also the color of the tips of the external tail-feathers. Dimensions. Total length, about 9½ inches; wing, 6½; tail, 5 inches. Hab. Eastern North America. Western? Canada (Dr. Hall); Cuba (Mr. Lembeye); Florida (Bartram). Spec. in Mus. Acad., Philada. Obs. This species is of common occurrence in the States on the Atlantic, and is universally known from its loud and often-repeated notes in the season of pairing and incubation. It is not recorded by our late naturalists and travellers to have been observed in the western regions of this continent, but the specimens described by Wagler as above were from Mexico, and were either this species, or a near relative. To _Caprimulgus macromystax_ we shall more particularly allude under the head of obscure species of this family. 3. Antrostomus Nuttallii. (Aud.) Nuttall’s Whip-poor-will. Caprimulgus Nuttallii. Aud., Orn. Biog., V. p. 335. (1839.) Aud., B. of Am., Oct. ed., VII. pl. 495. Small, aberrant; wing long; third quill longest; legs rather long; tail moderate; upper-parts brownish-black, mottled and spotted with ashy white and reddish fulvous; wing-coverts tipped with pearly ashy white; under-parts with transverse stripes of brownish-black and yellowish-white; under tail-coverts pale reddish fulvous; quills with alternate transverse bars of brownish-black and handsome reddish fulvous; middle feathers of the tail same colors as other upper parts; other tail feathers brownish-black, with irregular bars and lines of dark cinereous, and widely tipped with silky white; collar on the neck before silky white. Female similar, but with the colors paler, and the white of the throat and tail tinged with pale fulvous. Dimensions. Total length, about 7 inches; wing, 5¾; tail, 3¼ inches. Hab. Western North America, Rocky Mountains (Audubon); Oregon (U. S. Ex. Exp. Vincennes); Washington Territory (Dr. Cooper); Texas (Mr. J. H. Clark). Spec. in Mus. Acad., Philada., and Nat. Mus., Washington.