160 ANATOMY OF THE RABBIT. 
of the thorax, the corresponding surfaces are more nearly ventral 
and dorsal. Of its three borders, one, the superior border (margo 
superior), is directed toward the occiput; another, the vertebral 
border (margo vertebralis), toward the vertebral column; and the 
third or axillary border (margo axillaris), toward the armpit. 
The corresponding angles are medial (superior), inferior, and 
lateral (glenoid). The lateral surface bears a stout bony plate, 
the scapular spine (spina scapulae), which arises from the body of 
the bone through about two-thirds of its extent, and ends ven- 
trally in a free projection, the acromion. The posterior margin 
of the acromion bears a backwardly-directed process, the meta- 

Fic. 66. Lateral surface of the left scapula: a., acromion; a.i., a.l., and a.m., 
inferior; lateral, and medial angles; c.g., glenoid cavity; c.s., neck of the scapula; 
f.s. and f.i., supraspinous and infraspinous fossae; m., metacromion; m.a., m.s., and 
m.v., axillary, superior, and vertebral borders; p.c., coracoid process; ‘s.s., scapular 
spine. 
cromion (processus hamatus). Through the presence of the 
scapular spine, the lateral surface of the bone is divided into two 
areas for muscular attachment. One of these, the supraspinous 
fossa (fossa supraspinata), lies in front of the spine, the other, 
the infraspinous fossa (fossa infraspinata), behind it. The 
infraspinous fossa is the more extensive one. The medial surface, 
onthe other hand, presents a single large shallow depression, the 
subscapular fossa (fossa subscapularis), 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 
