186 SKELETON. 



the glenoid cavity, about an inch from its internal margin. The 

 upper surface of the coracoid process is rough and undulated; 

 below it is concave, forming an arch under which passes the 

 sub-scapularis muscle. On the clavicular side of its base is a 

 tuberosity, from which arises the conoidal ligament. The ex- 

 tremity is marked by three surfaces : the interior is for the in- 

 sertion of the pectoralis minor, the middle for the origin of the 

 coraco-brachialis, and the external for that of the short head of 

 the biceps. The acromial margin of the coracoid process gives 

 origin to the triangular ligament of the scapula, which is in- 

 serted into the acromion just below the face for the clavicle. 



The scapula is composed of cellular and compact substance. 

 The two laminae of the latter are in contact in the fossa supra- 

 spinata, and infra-spinata; from which cause the bone is diapha- 

 nous at these points* 



Of the Clavicle, (Clamcula, Clavicule.) 



The Clavicle is a long bone, situated transversely at the up- 

 per front part of the thorax, and extends from the superior ex- 

 tremity of the sternum to the acromion of the scapula. It is 

 cylindrical in its middle third, flattened at its external, and 

 prismatic or triangular at its sternal extremity. Besides being 

 shorter, it is more crooked and robust in man than in woman, 

 and different individuals present it under considerable varieties 

 of curvature. The sternal two-thirds of it are convex in front, 

 and concave behind, while the humeral third is concave in 

 front, and convex behind: this double curvature induces anato- 

 mists to compare it with the letter S, though it is by no means 

 so crooked. 



We have to consider its superior and inferior face, its ante- 

 rior and posterior edge, and the two extremities. The superior 

 face is smooth, and does not present any marks of importance 

 excepting a depression near the sternum, for the origin of the 

 sterno-cleido mastoid muscle. The inferior face, near the ster- 

 nal end, has a rough surface, to which is attached the costo- 

 clavicular or rhomboid ligament: about fifteen lines from the 

 humeral extremity is a rough tubercle for the attachment of the 

 coraco-clavicular or conoid ligament. Between the two ends, 



