ANATOMY OF THE HOUSE. 483 
same ridge, which both Bourgelat and Girard regard as another 
muscle. 
Action .—To assist in the flexion of the humerus; and, at the 
same time, to roll it outwards. 
2.—INTERNAL SCAPULAR REGION 
Contains but one muscle. 
sub-scapularis. — ( Sub-scapulo-trochineus.) 
Situation. —Occupying the venter scapula. 
Form. —Triangular; broad, flattened, thin in substance. 
Attachment .—Superiorly, to the surface of the venter scapulae, 
and to the anterior and posterior costae; interiorly, 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, interiorly, 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. —( Subscapulo-humeralis .) 
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. 
