Radius: Almost perfectly straight, but a little inclined toward ulna at oblique proximal end; scarcely expanded at distal end, which is lower externally than internally. Ulna: Much slenderer than radius, rounded triangular in section, not expanded at distal end, where the margin is lowest externally. Olecranon well developed, thin, and pointed proximally. Carpals: Five; two on ulna side, two median and one on radial side in line with first metacarpal. The proximal middle bone (intermedium) extends much farther proximally than those on each side of it. Metacarpals: Metacarpal III longest, metacarpal II broadest. Metacarpal I oblong, or rather conical, with a lateral enlargement, and situated in line with the distal row of carpals. Digits: First phalange of first digit short and conical. _Newport_ (male).—Fore limb considerably longer and more massive than that of the Barnegat skeleton but similar otherwise, except as follows: Humerus: Head rather larger and less inclined. Deltoid ridge more prominent. Radius: Broader proximally and rounded at distal end, where it extends outward beyond the carpal bones. Ulna: Thicker, and olecranon less pointed. Carpal bones: Middle carpal bone not extending farther proximally than those on either side of it. Metacarpals: Metacarpal I nearly square, third longest, second to fourth more constricted. Digits: First phalange of first digit long and cylindrical. Phalangeal formula: I, 1; II, 6; III, 6; IV, 4; V, 2. Measurements of the skeletons above described are as follows: _Dimensions of four skeletons of Ziphius cavirostris._ Column headings: A: Barnegat City, New Jersey. 20971 U.S.N.M. female, adult. B: Newport, Rhode Island. 49599 U.S.N.M. male, adult. C: Charleston, South Carolina. 21975 U.S.N.M. female, young. D: Bering Island. (Vertebræ) young.