212 Anatomy of the Rabbit. 



(f) The subscapularis. Origin: Entire medial surface of the 

 scapula. Insertion: Lesser tubercle of the humerus. 



(g) The teres major. Origin: Dorsal portion of the axillary 

 border of the scapula. Insertion: In common with the 

 latissimus dorsi on the anterior surface of the humerus. 



(h) The teres minor. Origin: Ventral portion of the axillary 

 border of the scapula. Insertion: Greater tubercle. 



The muscle is closely associated with the infraspinatus but is 

 separated from the teres major by the tendon of origin of the long head 

 of the triceps. 



(i) The coracobrachialis. Origin: Coracoid process. In- 

 sertion: Distal portion of the upper third of the humerus on 

 its medial surface. 



5. Muscles arising from the scapula and humerus and inserted 

 on the proximal ends of the radius and. ulna (extensors and flexors 

 of the forearm). (Figs. 34, 35. 74). 



A. Extensor (anconaeus) group. The muscles arise for the 

 most part behind the axis of the humerus, and are inserted on the 

 olecranon. 



(a) The extensor antibrachii parvus (anconaeus quartus). 

 Origin: Fascia of the medial surface of the humerus. Inser- 

 tion: Medial surface of the olecranon. 



The muscle should be divided, or detached from its origin, and re- 

 flected. 



(b) The anconaeus minimus (epitrochleor anconaeus). 

 Origin: Medial epicond.yle of the humerus. Insertion: 

 Medial surface of the olecranon 



(c) The triceps brachii. Origin in three portions: 



Caput longum (anconaeus longus) : Ventral portion of the 

 axillary border of the scapula. 



Caput laterale (anconaeus lateralis) : Greater tubercle and 

 related portion of the lateral surface of the humerus. 

 Caput mediale (anconaeus medialis) : Posterior surface of 

 the humerus. 

 The three portions are almost separate muscles. Insertion 

 on the olecranon. 



