526 



MAMMALIAN ANATOMY 



surface, wide laterally and medially, but narrower in the middle. Its 

 outer part is concave and forms the subclavian groove for the sub- 

 clavius muscle. On the inner part at the medial end, in front, is an 

 oval facet for articulation with the cartilage of the first rib, and behind, 

 the larger rough rhomboid impressions. The posterior surface is 

 smooth and deeply concave from within outward. It is in relation 

 with the brachial plexus of nerves and the subclavian vessels. To 

 its inner part is attached the sterno-hyoid muscle. Near the middle 

 is the chief nutrient foramen of the bone. The anterior surface is 

 very wide at the inner end and narrow at the outer end. Its inner 

 half or more is divided lengthwise by a strong pectoral line ; the part 

 above the line, sometimes called the superior surface, is more or less 

 roughened behind for the attachment of the sterno-cleido-mastoid 

 muscle ; to the part below the line, sometimes called the anterior sur- 

 face, is attached the pectoralis major muscle. The outer half of this 

 surface is smooth and covered only by the platysnia myoides muscle 

 and the skin. The terminal sternal surface is occupied by an articular 

 facet, which is convex from above downward and concave from before 

 backward ; it joins the clavicular facet on the superior margin of the 

 manubrium of the sternum. 



THE SCAPULA. 



FIG. 417. 



Vertebral Column. 



Hymd. 



Clavicle. 

 Sternum. 



Radius. 



Metacarpus. 



^Carpus. 



I Metatarsus. 



^Phalanges, "tg^ Phalanges. 



THE SKELETON OF THE CAT. (LEFT SIDE ONLY.) 



General Description. The Scapula?, the principal elements in 

 the shoulder girdle, are large, flat bones lying on each side of the 



