The body of the ulna becomes triangular distad. The distal end is slightly larger than the shaft just proximad of it, and bears on its radioventral side a hemispherical head for articulation with the radius. Distad of the head the bone continues as the flattened =styloid= process (_m_), which projects distad from its dorsolateral side and is smooth on the medial side of its apex, for articulation with the cuneiform bone of the wrist. =Carpus= (Fig. 51).--The carpus (wrist) consists of seven bones arranged in two rows, three in the proximal row and four in the distal row. Beginning on the medial side of the hand (thumb or radial side), the first bone in the proximal row is the =scapholunar= (_a_) (equal to the scaphoid or navicular and lunar of the human hand). It articulates with the radius. The next is the =cuneiform= (_b_), articulating with the styloid process of the ulna, and the next, which is attached to the cuneiform and projects freely ventrad, is the =pisiform= (_c_). In the distal row the bone on the radial side is the =trapezium= (_d_); the next is the trapezoid (_e_), the next the os magnum (_f_), and the last the unciform (_g_). The distal row articulates with the metacarpals or bones of the palm of the hand (1-5). In the kitten the scapholunar is represented by three bones, the =scaphoid= or navicular, on the radial side, the =lunare=, between the scaphoid and the cuneiform, and a =centrale=, which lies distad of the other two. _Scapholunar Bone._ _Os scapholunaris_ (Fig. 51, _a_).--The scapholunar is a quadrangular bone with the ventroradial angle produced into a blunt process. Its proximal surface is smooth and articulates with the distal end of the radius. The distal end is marked by oblique ridges and articulates with the unciform, os magnum, trapezoid, and trapezium. The ulnar surface articulates with the cuneiform, and the dorsal surface of the ventroradial process with the radial sesamoid. _Cuneiform Bone._ (_Os triquetrum BNA_) (Fig. 51, _b_).--The cuneiform bone has the form of a flattened pyramid. Its base articulates with the unciform, its proximoulnar surface with the pisiform except at its dorsal margin, where it articulates with the styloid process of the ulna. On its proximoradial surface is a smooth facet for articulation with the scapholunar. _Pisiform Bone._ _Os pisiforme_ (Fig. 51, _c_).--The pisiform bone is about twice as long as broad, with enlarged ends. Its dorsal end articulates with the cuneiform, and on its proximal surface, separated from the above by a smooth ridge, is a smooth facet for articulation with the styloid process of the ulna. [Illustration: FIG. 51.--CARPUS, METACARPUS, AND PHALANGES, DORSAL SURFACE. _a_, scapholunar bone; _b_, cuneiform; _c_, pisiform; _d_, trapezium; _e_, trapezoid; _f_, os magnum; _g_, unciform; _h_, radial sesamoid; _i_, proximal phalanges; _j_, second phalanges; _k_, distal phalanges; 1, 2, 3, 4, 5, metacarpals in order from the radial side.]