78 



THE SKELETON OF THE HORSE 



tubercle (Tuberositas teres), to which the tendon of the latissimus dorsi and teres 

 major muscles is attached. The nutrient foramen is in the lower third of this sur- 

 face. The anterior surface is triangular, wide and smooth above, narrow and 

 roughened below. It is separated from the external surface by a distinct border, 

 which bears on its upper part the deltoid tuberosity (Tuberositas deltoidea). 

 From the latter a rough line curves upward and backward to the outer surface of 

 the neck, and gives origin to the external head of the triceps muscle. Below the 



Internal 

 tuberosity . 



External 

 tuberosity 



Internal 

 tubercle 



Curved line 



Deltoid 

 tuberosity — f 



Musculo-spiral 

 groove 



External con- 

 dyloid crest 



Coronoid fossa 



Internal 



epicondyle Internal 



condyle 



Fig. 45. — Left Humerus of Horse, In- 

 ternal Surface. (After Schmaltz, 

 Atlas d. Anat. d. Pferdes.) 



External 

 condyle 



Internal 

 epicondyle 



Olecranon fossa 



External 

 epicondyle 



Fig. 



46. — Left Humerus of Horse, External Surface 

 (After Schmaltz, Atlas d. Anat. d. Pferdes.) 



tuberosity the border inclines forward, becomes less salient, and ends at the coronoid 

 fossa. The posterior surface is rounded from side to side and smooth. 



The proximal extremity consists of the head, neck, two tuberosities, and the 

 bicipital groove. The head (Caput humeri) presents an almost circular convex 

 articular surface, which is about twice as extensive as the glenoid cavity of the 

 scapula, with which it articulates. In front of the head is a fossa, in which are 

 several foramina. The neck (Collum humeri) is well defined behind, but is prac- 

 tically absent elsewhere. The external tuberosity (Tuberculum majus) is placed 



i 



