MUSCLES OF THE SHOULDEK. 711 



tendon, which goes under the acromion process, adheres to 

 the capsular ligament, and is inserted into the middle face 

 of the greater tuherosity of the humerus. 



Function. To roll the os-humeri outward and backward. 

 To strengthen the capsular ligament and to draw it out of the 

 joint, in the outward movements of the arm. There is also 

 a hursa between the tendon of this muscle and the scapula- 

 Teres minor teres, round (Fig. 150,) is a small and 

 narrow muscle, and arises from the inferior costa of the 

 scapula at the lower margin of the infra spinatus, is in- 

 separably attached to, and in fact forms part of this latter 

 muscle. It extends from the cervix to about an inch of 

 the inferior angle, and adhering to the capsular ligament, 

 is inserted tendinous and fleshy into the outer face of the 

 great tuberosity of the humerus. 



Function. To rotate the arm outward, and draw it 

 downward and backward. 



The teres major (Fig. 224) is a flat muscle, and arises 

 from the inferior angle of the scapula upon its rough flat 

 surface. Forming a thick fleshy belly, it ascends forward 

 and outward, and terminates on the inner side of the arm 

 in a broad thin tendon, which is inserted along with the 

 tendon of the latissimus dorsi into the inner or posterior 

 edge of the bicipital groove. The tendon of the teres 

 FIG. 224. major is posterior, and extends lower 



down the arm than the latissimus. 



Function. To roll the arm in- 

 ward, and draw it backward and 

 downward. 



The sub-scapularis (sub, under; 

 scapula, shoulder-blade) is a broad 

 triangular muscle, which arises from the whole of the 

 venter, and the superior and inferior costse of the scapula. 

 Its fibres converge to the neck of the scapula, pass below 

 the coracoid process, adhere to the inferior part of the 

 capsular ligament, and terminate in a strong tendon, 



FIG. 224 represents the Muscles of the Shoulder. 1 Deltoid 2 Subscapu- 

 laris. 3 Teres major. 4 Triceps. 



