318 



THE MUSCLES. 



Fig. 181. 



of the scapulo-humeral articulation, the anterior face of the humerus, the coraco« 



hmneralis, and the articulation 

 of the elbow. It is covered : 

 1. By the supra-spinatus, be- 

 tween the two branches of 

 which it passes. 2. By a 

 special aponeurotic sheath, the 

 tensor of which is the above- 

 named muscle, with the pecto- 

 ralis magnus (see Fig. 179, 12, 

 in which this aponeurosis has 

 been partly preserved). This 

 sheath separates the flexor 

 brachii from the mastoido- 

 humeralis, the pectoralis trans- 

 versus, and from its congener 

 — the short flexor. 



Action. — This muscle is a 

 flexor of the forearm, and a 

 tensor of the antibrachial 

 aponeurosis. It acts, besides — 

 through the cord which tra- 

 verses its entire length — as an 

 inextensible band that me- 

 chanically opposes the flexion 

 of the scapulo-humeral angle 

 while the animal is standing, 

 and when the forearm is main- 

 tained fixed by the contrac- 

 tion of the humero-olecranian 

 muscles. 



INTERNAL ASPECT OF LEFT ANTERIOR LIMB. 



1, Prolonging cartilage of scapula ; 2, inner surface of 

 scapula; 3, subscapulavis ; 4, adductor of the arm, or 

 teres internus ; 5, supra- or antea-spinatus ; 6, long 

 extensor of the forearm, or portion of the caput magnum ; 

 7, large extensor of the forearm, the other portion of the 

 caput magnum ; 8, middle extensor, or caput medium ; 



9, humeralis obliquus, or short flexor of the forearm ; 



10, coraco-humeralis ; 11, upper extremity of humerus ; 

 12, coraco-radialis, or flexor brachii ; 13, lower extremity 

 of humerus; 14, brachial fascia; 15, anterior extensor 

 of the metacarpus, or extensor metacarpi magnus ; 16, 

 belly and aponeurotic termination of the flexor brachii ; 

 17, ulna; 18, oblique flexor of the metacarpus; 19, 

 internal flexor of the metacarpus, or epicondylo-meta- 

 carpus; 20, radius; 21, tendon of the oblique extensor; 

 22, large metacarpal bone ; 23, flexor tendons of the 

 foot ; 24, suspensory ligament ; 25, internal rudimentary 

 metacarpal bone ; 26, extensor tendon of the foot ; 27, 

 metacarpo-phalangoal sheath ; 28, lateral cartilages of 

 the foot ; 29, podophyllae. 



ligament of the ulnar articulation, and those muscles of 

 epicondyle. 



2. Short Flexor of the 

 Forearm (Humeralis Ob- 

 liquus, Brachialis An- 

 Ticus, Humeralis Ex- 

 TERNUS) (Fig. 128, 12). 

 Synonyms. — Humero - cubitalis 

 obliquus, or humero-radialis — 

 Girard. {Humero-radialis — L^yh.) 

 Preparation. — Lay the limb on 

 its internal face, and remove the 

 abductors of the arm, the infra-spi- 

 natus, and the large and short ex' 

 tensors of tlie forearm, in order to 

 expose the middle and upper ex- 

 tremity 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 internal 

 the forearm which are attached to the 



