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A MANUAL OF ANATOMY 



the deep surface of the clavicular and upper sterno-costal portions ; 

 and (2) the internal anterior thoracic, the branches of which enter 

 the deep surface of the sterno-costal portion, after having pierced 

 the pectoralis minor. 



Blood-supply. — Branches of the thoracic axis. 



The upper fibres pass downwards and outwards, the middle 

 transversely outwards, and the lower upwards and outwards. 



Action. — Acting from its origin the muscle adducts the arm, 

 draws it forwards — that is to say, flexes it at the shoulder- joint 



Clavicular part of Pectoralis Major 

 Clavicular part of Deltoid ^ 



Coraco-brachialis 



Sterno-costal part 

 of Pectoralis 

 Major 



Latissimus Dorsi and 

 Teres Major 



Biceps 



Long Head of Triceps 



Brachialis Anticus 



Supinator Radii 

 Brevis 

 Bracbio-radialis 



Obliquus Ext. Abdominis 

 Serratus Magnus 



Internal Head of Triceps 



Brachialis Anticus 

 ..Pronator Radii Teres 



.Flexor Carpi Radial is 



Palmaris Longus 



— - Flexor Carpi Ulnaris 



Fig, 174. — The Superficial Muscles of the Front and Inner Side 

 OF THE Pectoral and Brachial Regions. 



(by its clavicular portion), and rotates it inwards. Acting from 

 its insertion it raises the trunk after the outstretched arm, as 

 in climbing a pole, and it elevates the upper ribs in forced 

 inspiration. 



The upper border of the muscle is related to the deltoid, from 

 which it is separated by a triangular interval for a short distance 

 below the clavicle, and the cephalic vein and humeral artery inter- 

 vene between the two. The lower border forms the anterior fold 

 of the axilla. Sometimes there is a muscle, called the sternalis, 



