SUBSCAPULARIS MUSCLE. 



241 



fibres of the serratus magnus are collected. On the outer surface of the 

 inferior angle lies the teres major (fig. 79, o) which will be subsequently 



seen. 



The insertion of the small pectoral muscle into the fore part of the 

 upper surface of the coracoid process may be ascertained at this stage of 

 the dissection (fig. 73, F). 



Fig. 73. 



A. Subscapularis. 



B. Teres major. 



c. Latissimus dorsi. 



D. Serratus magnus. 



E. Omo-hyoideus. 



F. Pectoralis minor. 



G. Biceps. 



H. Coraco-brachialis. 

 a. Supra-scapular artery. 

 1. Supra-scapular nerve passing through 

 the notch. 



VIEW OF THE SruscAPCi.ARis AND THE SURROUNDING MUSCLES. The other muscles fixed into 

 the base of the scapula as shown in fig. 74. 



Dissection. By the separation of the serratus from the subscapularis a 

 thin fascia comes into view, which belongs to the last muscle, and is fixed 

 to the bone around its margins ; after it has been observed, it may be re- 

 moved. 



The subscapularis muscle is to be followed forwards to its insertion into 

 the humerus. Next, the axillary vessels and nerves, and the offsets of 

 these to the muscles, should be well cleaned. 



The SUBSCAPULARIS MUSCLE (fig. 73, A) occupies the under surface 

 of the scapula, and is concealed by that bone when the limb is in its 

 natural position. The muscle arises from the concave surface on the 

 ventral aspect of the scapula, except at the angles, and this attachment 

 reaches forwards nearly to the neck ; it is united also to the ridges of the 

 bone by tendinous processes. Externally it is inserted by a tendon into 

 the small tuberosity of the humerus, and by fleshy fibres into the neck for 

 nearly an incli below that process. 



By one surface the muscle bounds the axilla, and is in contact with the 

 axillary vessels and nerves and the serratus magnus. By the other, it 

 rests against the scapula arid the shoulder joint ; and between its tendon 

 and the root of the coracoid process is a bursa, which communicates gene- 

 rally with the synovial membrane of the joint. The lower border projects 

 much beyond the bone ; it is contiguous to the teres major, the latissimus 

 16 



