MUSCULAR SYSTEM. 135 



Attachment. — Superiorly, to the surface of the venter scapulae, 

 and to the anterior and posterior costee ; inferiorly, to the lesser 

 tubercle of the humerus, and to the capsular ligament of the 

 shoulder joint. 



Relations. — Externally, with the bone; internally, with the 

 serratus ; anteriorly, with the pectoralis parvus ; posteriorly, with 

 the teres major. 



Direction. — Fan-like; the fibres converging- from above to 

 one and the same point below. 



Structure. — Superior attachments partly tendinous, but mostly 

 fleshy ; surface, partly aponeurotic ; middle intersected by ten- 

 dinous septa : its fleshy fibres, inferiorly, everywhere invest the 

 capsular ligament, there being interposed between these parts a 

 bursa mucosa. 



Action. — To assist in the extension of the shoulder joint, and 

 to turn the os humeri inwards. 



3.— POSTERIOR SCAPULAR REGION. 



TERES MAJOR. — Subscopulu-IiumeraHs. 



Situation. — Behind and below the subscapularis. 



Form. — Elongated ; flattened : about two inches in breadth. 



Attachment. — Superiorly, to the posterior angle of the scapula, 

 and also to the posterior costa : inferiorly, to the inner and upper 

 part of the body of the humerus. 



Relations. — Externally and posteriorly, with the triceps ; an- 

 teriorly, with the subscapularis and posterior costa of the scapula ; 

 internally, with the pectoralis magnus and latissimus dorsi. 



Structure. — Scapular attachment, fleshy and tendinous; belly, 

 fleshy ; surfaces, in part aponeurotic ; inferior termination, an 

 aponeurotic tendon. 



Action. — To assist in flexing the shoulder-joint; and to incline 

 the humerus inwards. 



TERES M I N OR. — Superscapulo-trochiterius. 



Situation. — Upon the outer and posterior part of the shoulder, 

 below and behind the postea-spinatus. 



Form. — Elongated; trilateral; flattened. 



Attachment. — Superiorly, to the posterior costa of the scapula: 

 inferiorly, to the ridge descending from the tubercle of the hu- 

 merus; and to the faschia a little above and to the outer side of 

 the end of the arm. 



Relations. — Anteriorly and superiorly, with the postea-spina- 

 tus; posteriorly and inferiorly, with the triceps: above with the 

 scapula ; below, with the humerus : externally, with the panni- 

 culus. 



