Sheath Bill
in ornithology, the genus Chionis, made known by the naturalists of Cook's second voyage, a specimen of C. alba having been met with on New Year Island, on Dec. 31, 1774. It resembles a pigeon in size and general appearance; plumage pure white; bill yellow at base, passing into pink at tip; round the eyes the skin is bare, and dotted with cream-colored papillæ; legs bluishgray. In the Falkland Islands it is called the kelp pigeon. Another species was discriminated in 1842 by Dr. Hartlaub; it is smaller than C. alba, with similar plumage, but having the bill and bare skin of the face black and the legs much darker. The sealers of Kerguelen Land call it the sore-eyed pigeon, from its prominent fleshy orbit.