SCAPULAR MUSCLES. 



209 



magnus ; it is inserted ten- 

 din ously into the small tuber- 

 osity of the humerus, and by 

 fleshy fibres into the bone for 

 a short distance lower down. 

 Tendinous septa, attached to 

 the ridges of the subscapular 

 fossa, pass outwards in the 

 origin of the muscle, and 

 others are prolonged inwards 

 from the tendon of insertion. 



Fig. 175. SUPERFICIAL MUSCLES 

 OP THE SHOULDER AND UPPER 



LlMB, SEEN FROM BEHIND. % 



a, acromion ; b, base of the sca- 

 pula ; c, tendon of the trapezius 

 muscle over the triangular surface 

 of the spine of the scapula ; d, 

 olecranon of the ulna ; e, external 

 condyloid eminence ; /, lower end 

 of the ulna ; 1, trapezius ; 2, acro- 

 mial part of deltoid ; 2', the part of 

 the same muscle rising from the 

 spine of the scapula ; 3, rhom- 

 boideus major ; 4, infraspinatus ; 

 5, teres minor ; 6, teres major ; 7, 

 latissimus dorsi ; +, triangular 

 space between the trapezius, rhom- 

 boid and latissimus ; 8, triceps ex- 

 tensor cubiti ; 8', its outer head ; 

 8", part of its inner head ; 9, an- 

 coneus ; 10, part of the brachialis 

 anticus ; 11, supinator longus ; 12, 

 extensor carpi radialis longior. The 

 explanation of the remaining refer- 

 ences will be found in the descrip- 

 tion of fig. 182. 



The tendon of this muscle is in- 

 corporated with the capsule of the 

 shoulder-joint, and between its 

 upper margin and the coracoid 

 process is a bursa usually commu- 

 nicating with that joint. Ante- 

 riorly it is in contact at ^its origin 

 with the serratus magnus, and is 

 covered at its insertion by the 

 coraco-brachialis and biceps, while, 

 in the interval between, it forms 

 part of the posterior wall of the 

 axilla. 



The supraspinatus muscle 

 arises from the whole surface 

 of the supraspinous fossa of 

 the scapula as far forward as 

 the outer extremity of the 

 spine, and from an aponeurosis, 

 by which it is covered. It 



Fig. 175. 



