MUSCLES 35 



of inner surface of humerus ; some of the upper fibres join a 

 fibrous arch which is attached above to the small tuberosity(x) 

 (Musculo-cutaneous). [Flexes and adducts shoulder-joint.] 

 Brachial vessels to inner side. 



Biceps : Long or glenoid head. From scapula at upper border 

 of glenoid cavity, and from glenoid ligament, within the 

 shoulder-joint(T). Short or coracoid head. Apex of coracoid 

 process of scapula(x) rough and hinder part of tubercle of 

 radius(i) and fascia of forearm (Musculo-cutaneous). [Flexes 

 shoulder, flexes elbow, supinates radius.] A bursa is placed 

 on the smooth and fore part of tubercle. Inner border, the guide 

 to brachial vessels below middle of humerus. A broad band, the 

 semilunar fascia, is given off from inner side of tendon opposite the 

 elbow-joint, covering brachial artery and joining deep fascia of fore- 

 arm. 



Brachialis anticus : lower half of outer and inner surfaces 

 of shaft of humerus, embracing insertion of deltoid, all inner 

 intermuscular septum, and upper part of outer intermuscular 

 septum (F) rough surface in front of coronoid process of 

 ulna(T) (Musculo-cutaneous, Musculo-spiral). [Flexes elbow.] 

 Brachial artery, median, musculo - spiral and musculo - cutaneous 

 nerves lie on it. 



POSTERIOR HUMERAL REGION. 



Triceps : Long or middle head. Depression on axillary border 

 of scapula, close beneath glenoid cavity(x). External head. 

 From root of great tuberosity to musculo-spiral groove on 

 posterior surface of humerus(p). Internal head. Posterior 

 surface of shaft of humerus, by side of and below musculo- 

 spiral groove, internal and external intermuscular septa(p) 

 posterior surface of olecranon process of ulna(x) (Musculo- 

 spiral). [Extends and adducts shoulder, extends elbow.] 

 Bursa is placed between the tip of process and tendon. 



Sub-anconeus : by two fasciculi just above olecranon fossa 

 of humerus(F) synovial sac of elbow-joint(F) (Musculo-spiral). 

 [Raises synovial membrane out of olecranon fossa in extension 

 of elbow.] 



OF FOREARM ANTERIOR, (a) Superficial Layer. 



The deep fascia of the forearm, continuous above with fascia 

 of arm, is attached posteriorly to subcutaneous edge of ulna, 

 and invests the muscles in this region. 



Anterior annular ligament (v. p. 13) is continuous by its upper 

 border with the deep fascia of the forearm. 



3-2 



