DISSECTION OF THE DOG 



127 



from the aponeurotic origin of the deltoid and from the long head of the 

 triceps. On the lateral aspect of the shoulder-joint the muscle gives place to a 

 flattened tendon which is attached to a ridge on the lateral face of the tuber- 

 culum majus after having played over a smooth area covered by cartilage, a 



m. infraspinatus 



m. triceps brachii. 

 Caput longum 



a. circumflexa 

 humeri posterior 



a. profunda _ _ _ — 

 brachii 



to. anconeus 



to. flexor carpi 

 ulnaris 



to. extensor carpi 

 ulnaris 



to. supraspinalus 



y 



to. teres minor 



n. axillaris 



to. triceps brachii. 



Caput mediale 



to. brachialis 



n. radialis 



to. biceps brachii 



- - - n. radialis. Ramus profundus 



- n. radialis. Ramus superficialis 

 ra, extensor carpi radialis 



_ to. extensor digitorum communis 

 jm. extensor digiti quinii 



Fig. 48. — Dissection of the arm after removal of the deltoid and the lateral head of the triceps muscle. 



synovial membrane further reducing the friction. Demonstrate this arrange- 

 ment by cutting the tendon across close to its commencement, and turning 

 back the two ends. This has the further advantage of showing a greater 

 amount of the teres minor muscle. 



M. teres minor. — The narrow, and somewhat rounded, teres minor lies 



