256 TBM MUSCLES. 



process by a superior, round, and thick tendon (Fig. 85, 6) that reaches the 

 bicipital groove, on which it is moulded in becoming fibro-cartilaginous, and 

 over which it glides by means of a synovial sac, to be inflected backwards 

 and confounded with the body o£ the muscle.' Its inferior tendon, extremely 

 short and strong, terminates on the superior and internal tuberosity of the 

 radius— the licipital tuberosity — in uniting itself to the capsular ligament of 

 the elbow joint, and insinuating itself beneath the internal ligament of this 

 articulation. ' At its origin, this tendon gives off a somewhat resisting 

 fibrous band, which is spread over the surface of the anterior extensor of 

 the metacarpus, and is confounded with the antibrachial aponeurosis. 



Relations. — The coraco-radialis covers an adipose cushion which sepa- 

 rates it from the capsule of the scapulo-humeral articulation, the anterior 

 face of the humerus, the coraco-humeralis, and the articulation of the elbow. 

 It is covered : 1, By the superspinatus, between the two branches of which 

 it passes ; 2, By a special aponeurotic sheath, whose tensor is the above- 

 named muscle, with the sterno-trochineus (see Fig. 114, 12, in which this 

 aponeurosis has been partly preserved). This sheath separates the coraco- 

 radialis from the mastoido-humeralis, the sterno-aponeuroticus, and from its 

 congener, the short flexor. 



Action. — This muscle is a flexor of the fore-arm, and a tensor of the 

 antibrachial aponeurosis. It acts, besides, through the cord which traverses 

 its entire length, as an inextensible band that mechanically opposes the 

 flexion of the scapulo-humeral angle while the animal is standing, and when 

 the fore-arm is maintained fixed by the contraction of the humero-olecranian 

 muscles. 



2. Short Flexor of the Fore-arm. (Fig. 85, 12.) 



Synonyms. — Sumero-cubitalis obliquus, or humero-radialis — Girard. {Bumeralis 

 externus — Percivall. Swnero-radialis — Leyh.) 



Preparation. — Lay the limb on its internal face, and remove the abductors of the 

 arm, the subspiuatus, and the large and short extensors of the fore-arm, in order to 

 expose the middle and upper extremity of this muscle. Then turn the limb on its 

 external face to dissect the inferior extremity. To study it in all its details, it is a good 

 plan to cut through the interna] ligament of the ulnar articulation, and those muscles of 

 the fore-arm which are attached to the epioondyle. 



Form — Structure — Situation — Direction. — This is a very thick muscle, 

 almost entirely fleshy, voluminous in its superior part, and constricted 

 inferiorly. It is lodged in the twisted furrow of the humerus, the direction 

 of which it exactly follows as it turns round the bone to cover, successively, 

 its posterior face, external face, anterior face, and the capsule belonging to 

 the elbow articulation, until it finally reaches the inner side of the radius.* 



Attachments. — The muscular fibres entering into its composition have 

 their fixed insertion on the posterior face of the humerus, below the articular 

 head. They terminate, inferiorly, on a flat tendon, which they almost 

 entirely cover. This tendon glides in a transverse" groove situated on the 

 inner face of the radius, below the bicipital tuberosity, and afterwards 

 passing under the internal ligament of the elbow joint, it divides into two 

 very short fasciculi ; one of these goes to the radius, and the other to the 

 ulna, where it is mixed up with the bundles of aroiform fibres, which unite, 

 on the inner side, the two bones of the fore-arm. 



Belations.—We already know the parts this muscle covers. It is covered, 

 inwardly, by 'tbe adductor of the arm and the middle extensor of the fore- 

 arm ; posteriorly and externally, by the large and short extensors of that 

 ray. - Its inferior extremity, comprised between the anterior extensor of the 



