MUSCLES 35 



deltoid muscle, on the deltoid ridge of the hu- 

 merus. (Plates II. and III.) 



11. The Epitrochlear is a thin, flat muscle on the 

 inner side of the fore-arm. It arises partly from 

 the fascia of the scapula, just below the insertion 

 of the posterior trapezius, and partly by muscular 

 fibres from a subjacent muscle, the latissimus dor- 

 si. It is inserted by fascia on the inner side of the 

 olecranon process of the ulna. (Plate II.) 



Reflect the deltoid, levator claviculce, and latissi- 

 mus dorsi muscles. 



12. The Supraspinatus is the large, thick muscle 

 which fills the entire supraspinous fossa of the 

 scapula and projects considerably over its anterior 

 border. Its fibres originate from the entire fossa, 

 the anterior side of the spine of the scapula, and 

 the acromion process. They are inserted by a 

 strong tendon into the great tuberosity of the 

 humerus. (Plates III. and IV.) 



13. The Infraspinatus Muscle occupies the infra- 

 spinous fossa of the scapula. Its fibres arise from 

 the whole fossa, the posterior side of the spine of 

 the scapula, and the acromion and metacromion 

 processes. They converge into a strong tendon, 

 which is inserted on the outer side of the great 

 tuberosity of the humerus, beside the insertion of 

 the supraspinatus muscle. (Plate III.) 



14. The Teres Major is a thick muscle lying 

 along the axillary margin of the scapula. It has 

 its origin on the upper third of the axillary border 



