44 



ANATOMY IX A NUTSHELL. 



consists of oblique fibers which arise in a bipenniform manner from the sides 

 of tendinous intersections, generally four in number, which are attached above 

 id the acromion process and pass downward parallel t<> one another in the sub- 

 stance of the muscle. The portion of the muscle which arises from the clavicle 

 and the -pine of the scapula are no1 arranged in this manner, bu1 pass directly 

 from i heir origin to their insertion. 



Insertion. (Plate XXIII.) The fibers of this muscle converge to- 

 wards their insertion, the middle passing vertically, the anterior obliquely 

 backward, and the posterior obliquely forward; they unite to form a thick ten- 



PLATE XIII 



TRANSVERSE LIGAMENT 



Acromio-Clavicular Articulation and Shoulder-Joint. 



don which is inserted into a rough triangular prominence on the middle of the 

 outer side of the shafl of the humerus. At its insertion is given oft' an expan- 

 sion t<> the deep fascia of the arm. The oblique filters arising from the tendi- 

 nous intersections, generally three in number, pass upward from the intersec- 

 tion of the muscle ami alternate with the descending septa. 



Action. To raise the arm ami helps to draw it forward ami backward. 



Xi.i;\ i. Si ppli ( Jircumfiex. 



Blood Supply. rPosterior circumflex ami acromial thoracic arteries. 



