200 ANATOMY OF THE RABBIT 



ion, the subscapular fossa (fossa subscapularls), which is triangular 

 in shape and occupies practically the entire surface. The apex 

 or lateral angle of the scapula, sometimes termed the head of the 

 bone, is expanded to a considerable extent in comparison with 

 the slender portion — the so-called neck of the scapula (collum 

 scapulae) — connecting it with the body of the bone. It bears a 

 concave depression, the glenoid cavity (cavitas glenoidalis), for 

 articulation with the humerus. The articulating surface is borne 

 chiefly on that part of the bone corresponding to the axillary 

 border, but it also extends in an anterior direction to the base of 

 an overhanging projection, the coracoid process (processus cora- 

 coideus). The free portion of the latter forms a blunt, hook-like 

 projection mediad. It represents the separate coracoid bone of lower 

 terrestrial vertebrates (p. 61). 



In the fresh condition, the vertebral border of the scapula 

 bears a plate of cartilage, the suprascapula, which is about three- 

 quarters of a centimetre wide near the inferior angle and tapers to 

 a point towards the medial angle. 



The Clavicle 



The clavicle (clavicula) is imperfectly developed in the rabbit, 

 consisting of a slender, curved rod of bone, tipped by cartilage, 

 which lies in the interspace between the manubrium sterni and 

 the head of the humerus. It occupies only a portion of this inter- 

 space, being attached medially by the sternoclavicular ligament 

 and laterally by an acromioclavicular and a very slender coraco- 

 clavicular ligament, all three of which are considerably elongated. 

 The sternoclavicular ligament is nearly two millimetres in diameter 

 and fully twenty millimetres long, the acromioclavicular about 

 two millimetres by thirty-five millimetres, and the coracoclavicular 

 about twenty-five millimetres long. According to recent studies, 

 the so-called cleidohumeral ligament to which certain muscles are 

 attached (pp. 258 and 264) is merely a persistently fibrous inter- 

 section between tendons attached to the clavicle before reduction 

 of the latter occurred but is not a vestige of the clavicle or its 

 true ligaments. 



