208 ME. F. E. BEDDARD — CONTKIBUTIONS TO THE 



the deltoid. The area of origin of the teres major measures rather more than one inch 

 and a quarter in length. The muscle is flat and strap-shaped and of some thickness ; 

 it is inserted on to the humerus by a flat tendon, some of which, as has been already 

 explained, belongs to the latissimus dorsi; the line of insertion, which is just opposite 

 to that of the greater part of the insertion of the latissimus dorsi, measures about an 

 inch and a half. 



(16) Teres minor. — This muscle has an entirely fleshy origin partly from the axillary 

 border of the scapula, partly from the septum between itself and the infra-sjjinatus ; 

 the line of origin measures one inch and three-fifths ; it is inserted on to the head of 

 the humerus by an almost entirely fleshy insertion below, and separated by an interval 

 from, the insertion of the infra-spinatus. 



(17) Infraspinatus occupies the whole of the infra-spLnous fossa, to the greater part 

 of which, however, it is not attached ; it arises from the spine of the scapula up to the 

 head, from the posterior border, from the axillary border, and from the fascia covering 

 it ; it also arises from the septa between itself and the two teres muscles. Its tendinous 

 insertion is continuous with, and cannot be separated from, the insertion of supra- 

 spinatus and the ligament uniting the scapula with the humerus. 



(1 8) Supra-spinatus occupies the whole of the supra-spinous fossa. 



(19) Subscapularis covers and arises from nearly the whole of the subscapular fossa; 

 the insertion on to the humerus measures one inch and a quarter in length, the lower 

 part of the insertion below the tuberosity being fleshy. 



(20) Triceps. — This muscle has (excluding the dorso-epitrochlear) three heads of 

 origin. The middle or long head arises from the border of the glenoid cavity, and 

 from the inferior border of the scapula for an inch behind this ; this origin is chiefly 

 muscular, though tendinous where it is attached to the glenoid border ; its inferior 

 surface is covered by six or seven narrow tendinous bands which extend for a very short 

 way down the muscle. The outer head arises from the humerus commencing about 

 half an inch below the insertion of the teres minor: the origin of the inner head 

 commences a little below that of the outer head. 



(21) Brachialis anticus. — This muscle is large and fleshy ; it arises from a large 

 portion of the shaft of the humerus on both sides of the insertion of the deltoid; on 

 the inner side of the humerus the origin extends a little way above the origin of the 

 internal humeral head of the triceps ; it passes under a tendinous arch left in the 

 origin of the external humeral head of the triceps. The origin of the muscle is also 

 from the septum between itself and the external head of the triceps ; on the outer side 

 of the insertion of the deltoid the origin of the muscle does not extend forwards much 

 beyond the termination of the deltoid insertion, from this point downwards the origin 

 of the muscle occupies the whole of the inferior surface of the humerus, coming into 

 contact, on each side, with the origins of the triceps and supinator longus. Towards 

 the distal end of the attachment some of the fibres arise from a septum between itself 



