242 



THE SKELETON. 



the inner part is fraught with difficulty, the main danger being the risk of wounding the great 

 veins which are in relation with its under surface. 



The Scapula. 



The Scapula (ffxandvy, a spade) forms the back part of the shoulder girdle. It 

 is a large, flat bone, triangular in shape, situated at the posterior aspect and side of 



FIG. 194. Left scapular anterior surface, or venter. 



the thorax, between the second and seventh, or sometimes the eighth, ribs, its poste- 

 rior border or base being about an inch from, and nearly, but not quite parallel 

 with the spinous processes of the vertebrae, so that it is rather closer to them 

 above than below. It presents for examination two surfaces, three borders, and 

 three angles. 



The anterior surface, or venter (Fig. 194), presents a broad concavity, the sub- 

 scapular fossa. It is marked, in the posterior two-thirds, by several oblique 

 ridges, which pass from behind obliquely outward and upward ; the anterior third 

 is smooth. The oblique ridges give attachment to the tendinous intersections, and 

 the surfaces between them to the fleshy fibres, of the Subscapularis muscle. The 



