But in the ox and the horse it is quite otherwise. From the simplification of the skeleton of the hand, and the reduction of the number of movements which the bones that form it are able to execute, there naturally results a diminution of its muscular apparatus. Apart from the existence of muscular vestiges of but little importance, we can say that, in reality, the hand does not possess any muscles. On its palmar aspect are found only the tendons of the flexors of the digits, and as these tendons are large, and the hand long, they give origin to external forms which it is necessary to examine. [Illustration: FIG. 79.--LEFT ANTERIOR LIMB OF THE HORSE: EXTERNAL ASPECT. 1, Ulna of abnormal length.] [Illustration: FIG. 80.--LEFT ANTERIOR LIMB OF THE HORSE: EXTERNAL ASPECT. 1, Normal ulna.] In the horse, which we take as a type, the tendons of the flexors, after being retained in position at the carpus by a fibrous band, the _carpal sheath_, which recalls the anterior annular ligament of the human carpus, and having passed this region, descend vertically, remaining separated from the posterior surface of the metacarpus, so that the skin sinks slightly on the lateral parts in front of the thick cord which these tendons form. This cord is known by the name of _tendon_. The flexors then reach the fetlock, and occupy the groove formed by the peculiar arrangement of the two large sesamoid bones. They are retained in position at this level by a fibrous structure, which forms the metacarpo-phalangeal sheath. They then reach the phalanges, being directed obliquely downwards and forwards, as, moreover, the latter are also inclined. Then the tendon of the superficial flexor divides into two slips, which are inserted into the second phalanx, between which slips passes the tendon of the deep flexor, which in its turn goes to be inserted, in the form of an expansion, into the semilunar crest, by which the inferior surface of the third phalanx is divided into two parts.[30] [30] See, as regards this crest, in the paragraph relative to the hoof of the solipeds, the figures which represent the third phalanx, viewed on its inferior surface (Figs. 101 and 102, p. 258). The part which these tendons play is of great importance in the large quadrupeds. These tendons, in fact, in addition to the action determined by the contraction of the fleshy fibres to which they succeed, maintain the angle formed by the canon-bone and the phalangeal portion of the hand, and prevent its effacement under the weight of the body during the time of standing. Their strong development, and the position they occupy, make this understood, without it being necessary to insist on it further.