THE MUSCULAR SYSTEM Jl 



Teres Minor. Origin, upper two-thirds of the axillary 

 border of the scapula. Insertion, into the lower facet of 

 the greater tuberosity of the humerus. Action, rotates 

 the humerus outward. Nerve, circumflex. 



Teres Major. Origin, lower border of infraspinous fossa, 

 and is inserted into the bicipital groove of the humerus. 

 Action, draws the humerus downward and backward, when 

 raised also rotates it inward. Nerve, lower subscapular. 



Coracobrachialis. Origin, from the coracoid process of 

 the scapula. Insertion, middle of inner side of the 

 humerus. Action, draws the humerus forward and in- 

 ward, as well as elevates same. Nerve, musculocutaneous. 



Biceps Flexor Cubiti. Origin, by two heads: Short 

 head, from the coracoid process of the scapula; long head, 

 from upper margin of the glenoid cavity by a round tendon 

 continuous with the glenoid ligament. Insertion, by a 

 tendon into the back part of the tuberosity of the radius 

 and by an aponeurosis into the fascia of the forearm, which 

 renders this fascia tense. Nerve, musculocutaneous. 



Brachialis Anticus. Origin, anterior surface of the 

 humerus, embracing the insertion of the deltoid. In- 

 sertion, into the inferior surface of the coronoid process of 

 the ulna. Action, flexes the forearm. Nerve, musculo- 

 cutaneous and musculospiral. 



Triceps Extensor Cubiti. Origin, arises by three heads, 

 the long, external, and internal; long head, from the 

 glenoid fossa, the external, from the posterior surface of 

 the shaft of the humerus between the upper part of the 

 musculospiral groove and the insertion of the teres minor ; 

 internal, from the posterior surface below the musculo- 

 spiral groove. Insertion, into the olecranon process 

 of the ulna. Action, extends the forearm. Nerve, mus- 

 culospiral. 



Subanconeus. On'gw, above the olecranon fossa of the 

 humerus. Insertion, into the posterior ligament of the 



