26 



TOPOGKAPHICAL ANATOMY OF 



by the scapula and the humerus. It has a partly fleshy, partly 

 tendinous, origin from the axillary border of the scapula close to the 

 caudal angle, and a broad, aponeurotic origin from the spine of the 

 scapula. The tendinous aponeurosis can be raised from the under- 

 lying infraspinous muscle in the more distal part only. Elsewhere 



M. infraspinatus. M. supraspinatus. 



M. triceps brachii 

 (caput laterale). 



M. brachialis. 



M. anconasus. 



M. teres major. 



-- M. deltoideus. 



— M. extensor carpi radialis. 



— M. extensor digitorum 

 communis. 



Mm. flexores digitorum. 

 sublimis et profundus. 



M. extensor carpi ulnaris. 

 Fig. 13. — Lateral Aspect of the Humerus, with Areas of Muscular Attachment. 



the origin of the deltoid and the aponeurotic covering of the infra- 

 spinous are so intimately blended as to be one structure. 



The insertion of the deltoid is into the deltoid tuberosity of 

 the humerus. 



An imperfect division of the deltoid into two parallel portions 

 might lead to the assumption that in the horse, as in the dog and 

 the ruminants, the muscle consists of scapular and acromial parts. 

 There is, however, little justification for this assumption. It is more 



