Auk is the vernacular name for certain sea-birds of the family _Alcasæ_, known scientifically as species of the subgenera, _Alca_, _Fratercula_, _Mergulus_ and _Phaleris_. The true Auks, though properly oceanic birds, scarcely ever leaving the water except for the purposes of reproduction, can run, though awkwardly, on foot, when pursued on land. They breed in caverns or lofty cliffs, laying but one large egg. They feed on fish and other marine animals. The first of the genus _Alca_ is the Great Auk, remarkable for the imperfect development of its wings. It seldom leaves the regions bordering on the Arctic and Antarctic Circles. The wings, perfectly useless for flight, are very serviceable as oars. Mr. Bullock relates that during his tour to Northern Isles, one of them, with his four oars, left a six-oared boat of pursuers far behind. Newfoundland is one of their breeding places, and the Esquimaux make clothing of their skins. They are never seen beyond soundings; and seamen direct their measures according to their appearance. The length of the bird is less than three feet. The winter plumage, which begins to appear in autumn, leaves the cheeks, throat, fore part and sides of the neck white. In spring the summer change begins to take place, and confines the white on the head to a large patch, which extends in front and around the eyes; the rest of the head, the neck and upper plumage is of a deep black. [Illustration: [Alca torda.]] RAZOR-BILL. (_Alca Torda._) In the second species of _Alca_, the Black-billed Auk, Razor-bill, or Murre, the development of the wings is carried to the usual extent necessary for flight, though the bird uses them with great effect as oars, when swimming under water. They are diffused over the northern hemisphere on both continents; but they are particularly abundant in the higher latitudes. In England their eggs are esteemed a great delicacy, for salads especially, and on the coast of that country the “dreadful trade” of taking their eggs is actively carried on. In Ray’s Willoughby, the habits of the Razor-bill are thus described: “It lays, sits and breeds up its young on the ledges of the craggy cliffs and steep rocks by the seashore, that are broken and divided into many, as it were, stairs or shelves, together with the _Coulternebs_ and _Guillemots_. The Manks-men are wont to compare these rocks, with the birds sitting upon them in breeding time, to an apothecary’s shop—the ledges of the rocks resembling the shelves, and the birds the pots. About the Isle of Man are very high cliffs, broken in this manner into many ledges one above another, from top to bottom. They are wont to let down men by ropes from the tops of the cliffs, to take away the eggs and the young ones. They take also the birds themselves, when they are sitting upon their eggs, with snares fastened at the top of long poles, and so put about their necks. They build no nests, but lay their eggs upon the bare rocks.