370 



THE MUSCULATURE 



Processes extend over the greater and lesser tubercles. 



B. supracoracoidea. — A bursa sometimes found between the coracoid process and the 

 clavicle and the deltoid muscle. 



B. m. subscapularis. — Between the glenoid border of the scapula and the subscapularis 

 muscle. Communicates with the joint cavity. A small portion of this bursa may be isolated 

 adjacent to the base of the coracoid process (6. subcoracoidea) . 



B. m. infraspinati. — Between the tendon of the infraspinatus and the capsule of the joint 

 or the great tubercle. 



B. m. latissimi dorsi. — Constant between the tendons of the latissimus dorsi and the teres 



major. 



B. m. teretis majoris.- 



-Under the insertion of the tendon of the teres major muscle. 



B. PECTORAL MUSCLES AND AXILLARY FASCIA 



(Pigs. 357, 358, 360, 361, 388) 



The muscles belonging to this group are the pectoralis major, pectoralis 

 minor, and the subclavius. Of these, the largest and most superficial is the 



Fig. 358. — Deep Fascia of the Breast. (After Eisler). The Pectoralis Major Has 

 Been in Large Part Removed. 1, Deltoid; 2, Pectoralis Major, Abdominal Part; 3, 

 Pectoralis Minor; 4, Coraco-Brachialis. 



: EisLer, 



triangular pectoralis major ffig. 360), which arises from the secontl to the sixth 

 ribs, llie stcriniin, and the medial half of the clavicl(> and is inserted into the crest 

 of the greater tubercle of the humerus (pectoral ridge). Its lateral margin adjoins 

 the ventral margin of the deltoid, lieneath this muscle the much smaller triangu- 

 lar pectoralis minor (fig. 388) extends from near the ends of the second, third, 

 foinl h, and hfl li ribs to the tip of the coracoid process, while the small subclavius 

 (fig. 361) extends fron) the first rib upward and lateralward to the clavicle. 



The pectoral muscles and th(^ subclavius play a part in forc(Ml inspiration. 

 The pectoralis major also serves to adduct and Hex tlu; arm and rotate it 

 medial ward. 



()( the mu.scjcs included in this group, tlic two pectoral muscles are morphologically the most 

 closely related. They receive a iierve-.supply from the same set of nerves, the anterior thoracic 

 With them the subclavius, which has a separate nerve of its own, is closely associated. Cor- 



