102 OF THE MUSCLES. 



This muscle receives a tendon from the flexor brachii ; 

 which ultimately joins the Extensor Pedis ; and runs to its 

 insertion. Near to the extremity of the radius, the tendon 

 of this muscle is crossed by that of the Extensor metacarpi 

 obliquius. 



Extensor pedis {Plate III. 7) . Originates : from the outer 

 side of the humerus. Insertion. Into the os suffraginis ; 

 the OS corona; and the coronal process of the os pedis. 

 Action. To co-operate with the extensor metacarpi magnus ; 

 to extend the leg and foot ; and to counteract the influence of 

 the flexor pedis perforans and perforatus. 



Extensor suffraginis {Plate III. 9) . Arises: from the head 

 of the radius ; and from the junction of that bone with the 

 ulna. Inserted: into the head of os sufli'aginis by long 

 tendon. Action. To co-operate with the pedis in the ex- 

 tension of the leg ; and also to incline the pastern joint 

 outwards. 



Extensor metacarpi obliquus {Plate III. 8). Origin. 

 From the middle of the posterior margin of the radius. 

 Insertion. To the posterior of the knee, by tendon, which 

 can be traced to the pisiform bone. Action. To brace down- 

 ward the other extensors ; and to aid in extending the meta- 

 carpal bone. 



Flexor metacarpi internus {Plate III. 13). Origin. 

 From the condyle of the humerus. Insertion. To the back 

 of the head of the inner splent bone. 



Flexor metacarpi medius {Plate III. 14). Origin. From 

 the inner condyle of the humerus ; and by a slip of fibre 

 from the side of the ulna. Insertion. Into the trapezium. 



Flexor metacarpi externus {Plate III. 10). Origin. 

 From the external condyle of the humerus by tendon. In- 

 sertion. To the trapezium, by half its tendon ; and by the 

 other half to the outer splent bone. 



Action of the flexor metacarpi: the three contract in 

 unison, and serve to flex the radius ; helping to bend the 

 knee. 



Flexor pedis perforans et perforatus {Plate 111. 11. 

 15) arise: by tendon, fi'om behind the inner condyle of the 

 humerus. The fleshy belly, however, soon divides into two 

 halves ; from each of which proceeds a separate tendon. 

 These tendons, for distinction, are called the perforans and 

 the perforatus. 



