THOKACIC LIMBS 



535 



The glenoid cavity is gently concave in all directions, and for 

 the most part faces downward and forward ; the anterior smaller end, 

 however, faces downward and backward. This change in the direction 

 of the surface is due to the presence at its anterior end of a small 

 conical process known as the supraglenoid tubercle, to which the 



FIG. 422. 



Anterior Superior 

 Harder. 



Coracoid Process. 



CORACO-BRACHIALIS 



Coraco-humeral 

 Ligament. 



Glenoid Cavity articu- 

 lates with Head of 

 Humerus. 



Axillary Border. 



Acromial Head of 



DELTOID. 



Metacromion. 



LEFT SCAPULA, LOWER END. 



tendon of origin of the biceps muscle is attached. The surface of the 

 glenoid cavity is covered with a layer of articular cartilage, and its 

 margins, which in the dried bone are low and rounded, are heightened 

 and rendered thin by a cartilaginous ring, thus deepening the articular 

 cavity. 



The posterior surface (Fig. 421) of the head is the downward 

 continuation of the axillary border of the body, from which, however, 

 it slopes downward and inward. At the margin of the glenoid cavity 

 and a little above, it is strongly convex transversely ; above this again 

 it has the same direction as the vertebral border and faces backward 

 and inward ; it is excavated and roughened. It gives origin to the 

 teres minor and the scapular head of the triceps muscle. 



The anterior border, the continuation of the anterior superior 



