64 OUTLINES OP EQUINE ANATOMY. 



the anterior part of tlie neck ; to its wliole extent is 

 attaclied autea spinatus. This surface is increased by the 

 addition of the space, bounded anteriorly by the coraco- 

 scapular ligament, under which the dorsalis scapulae vessels 

 and nerve wind round the neck of the bone in passing to 

 or from this fossa. Fossa postea spinatus occupies two 

 thirds of the dorsum. It is bounded posteriorly by the 

 postero-inferior margin, superiorly by the postero- superior 

 margin, anteriorly by the spine. Superiorly it is smooth, 

 affording attachment to postea spinatus muscle, while the 

 inferior part, forming the posterior part of the neck, pre- 

 sents roughened lines extending obliquely upwards and 

 backwards from the inferior extremity of the spine. This 

 part gives attachment to scapulo-humeralis externus, and 

 presents grooves running from the posterior margin of the 

 bone to the inferior extremity of the spine, in which a 

 branch of the j^osterior scapular artery runs, sending off 

 the medullary artery of the hone through a foramen in this 

 region. The inner surface of the scapula is termed the 

 venter. It is concave from before backwards, the concavity 

 being most marked along the central line opposite the 

 spine. It is widest centrally, and superiorly terminates in 

 a point on reaching the cartilage of elongation. Inferiorly 

 it becomes flat in forming the neck, and again concave at 

 the inner surface of the coracoid process. Across the neck 

 of the bone, from behind forwards, run branching grooves 

 for arteries ; in other respects this concavity is smooth, 

 and it is continuous at its .upper part, anteriorly and 

 posteriorly with two other smooth surfaces, the anterior 

 of which is smallest and bounded by a roughened line 

 running downwards and backwards from the anterior edge 

 of the bone ; the posterior is bounded by a curved and 

 much rougher line extending from the posterior margin of 

 the bone up against the posterior angle. This smooth 

 surface, therefore, presents superiorly three points ; infe- 

 riorly it terminates at the margin of the glenoid cavity, 

 the inner surface of the coracoid process, and posteriorly 

 the roughened line which affords attachment to scapulo- 

 humeralis externus. It affords attachment to subscapularis, 

 between which, therefore, superiorly are two roughened 

 triangular surfaces, to which are attached the anterior and 

 posterior parts of serratus magnus. Along the inner 

 edge of the postero - superior roughened margin, and to 



