During a former voyage, on the 1st of January, 1829, I had an opportunity of examining a specimen of the _Diomedea fuliginosa_, Sooty Albatross, or quaker-bird, which was captured (by a hook and line, and a piece of salt pork by way of bait,) in latitude 39° 40′ south, and longitude 101° 5′ east. The wings, when expanded, measured six feet eleven inches from point to point. This was called _Pio_ by some of the sailors on board. The bill was of a beautiful shining black, with a distinct white membrane passing about two-thirds down the lower mandible; the legs were naked, and, as well as the feet, of a flesh colour; irides brown, and a circle of white feathers surrounded the orbit; the head, neck, throat, and back, were of a sooty colour; breast and abdomen greyish; wing coverts of a light grey; the pen-feathers of a light black; the tail feathers above of a sooty, inferiorly of a light grey colour; the feet had each three toes, united by a web, slightly serrated at the edges; the first toe had five, the second four, and the third three phalanges. On the 3rd of January another specimen was caught in latitude 40° 34′ south, and longitude 107° 18′ east, which differed in plumage from the preceding by having the sooty feathers on the head and back intermixed with white, which difference in plumage may have depended on age, as the sex of both birds was the same, being both males. I have subsequently had opportunities of examining numerous specimens, in many of which there were slight differences of plumage, but none particularly marking the sex, that I could discover. On the 5th of January, 1829, a specimen of the species named _Mollymawk_ by our sailors, the mountain Albatross of the Americans, was captured in latitude 40° 6′ south, and longitude 111° 49′ east. This I suspect only to be a young specimen of the large wandering Albatross. The bill was of a pale, dirty yellow; the head, neck, breast, and abdomen, were of a delicate and beautiful snowy whiteness; the back black, intermixed with brown, changing to snowy whiteness near the tail; tail feathers above black, underneath white; vent white; irides brown; orbits surrounded by a naked skin of a light bluish colour; black feathers at the inner angle of the eye; legs and feet of a flesh colour. The wings, when expanded, measured five feet from point to point.