Plumage generally close, rather compact, the feathers small and rounded; those on the head and neck blended and slightly glossed. A bare space between the bill and the eye, surrounding the latter, and extending an inch behind the angle of the mouth. The gular membrane also bare for a small breadth, extending two inches beyond the base of the mandible. About a quarter of an inch of the tibia bare. Wings very long, narrow, acute; primaries strong, narrow, tapering rapidly to a rounded point; first longest, second about a quarter of an inch shorter, the rest rapidly graduated; secondaries short, rather broad, rounded, with a minute acumen. Tail rather long, cuneate, of twelve narrow tapering feathers. Bill pale bluish-grey, tinged with green towards the base; the lines on the upper mandible blackish-blue; the bare space about the eye, and that on the throat, blackish-blue. Iris white. Tarsi, toes, and webs brownish-black, the bands of narrow scutella on the tarsus and toes light greenish-blue; claws greyish-white. The general colour of the plumage is white; the upper part of the head and the hind neck of a fine buff colour. Primary quills brownish-black, their shafts white toward the base. Length to end of tail 40-1/2 inches, to end of wings 38-1/4, to end of claws 41; extent of wings 75; wing from flexure 20-3/4; tail 10; bill along the ridge 4, along the edge of lower mandible 6; tarsus 2-2/12; first toe and claw 1-1/4; middle toe 3-8/12, its claw 7/12; outer toe 3-(8-1/2)/12; its claw 4/12. Weight 7 lb. The Female is similar to the male, but rather smaller. Young fully fledged. Plate CCCXXVI. Fig. 2. Bill light greyish-brown; the bare space around the eye pale greyish-blue. Iris green. Feet dusky, the narrow bands of scutella pale greyish-blue; claws greyish-white. The head, neck, and upper parts are chocolate brown, each feather with a terminal narrow triangular white spot; the lower parts greyish-white, spotted with greyish-brown; each feather having a broad terminal margin of that colour. The quills and tail-feathers are brownish-black. An individual shot in October measured as follows:— Length to end of tail 38 inches, to end of claws 32-1/2; extent of wings 72. Weight 3 lb. 4 oz. This individual, however, was very poor. Three individuals shot in the neighbourhood of Boston, Massachusetts, presented the following dimensions, which are here given as indicative of the difference of size frequently observed:— Length to end of tail, 38-3/4 38-3/4 37 wings, 37-1/2 37-1/2 35 claws, 34-1/4 34-1/2 33 Extent of wings, 73-1/2 72 68-1/2 Wing from flexure, 19-1/2 17-1/2 19-1/2