390 MUSCLES ON THE LEG. 



4. Flexor Longus Digitorum Pedis, Profundus, Perforans, 



Arises, by an acute tendon, which soon becomes fleshy from 

 the back part of the tibia, some way below its head, near the 

 entry of the medullary artery ; which beginning, is continued 

 down the inner edge of this bone by short fleshy fibres, ending 

 in its tendon ; also by tendinous and fleshy fibres, from the outer 

 edge of the tibia, and between this double order of fibres, the 

 tibialis posticus muscle lies enclosed. Having passed under two 

 annular ligaments, it then passes through a sinuosity at the 

 inside of the os calcis ; and about the middle of the sole of the 

 foot, divides into four tendons, which passes through the slits 

 of the perforatus ; and just before its division it receives a con- 

 siderable tendon from that of the flexor pollicis longus. 



Inserted into the extremity of the last joint of the four lesser 

 toes. 



Use. To bend the last joint of the toes. 



5. Tibialis Posticus, 



Arises, by a narrow fleshy beginning, from the fore and upper 

 part of the tibia, just under the process which joins it to the 

 fibula,; then passing through a perforation in the upper part of 

 the interosseous ligament, it continues its origin from the back 

 part of the fibula next the tibia, and from near one half of the 

 upper part of the last named bone ; as also, from the interos- 

 seous ligament, the fibres running towards a middle tendon, 

 which sends off a round one that passes in a groove behind 

 the malleolus internus. 



Inserted, tendinous, into the upper and inner part of the os 

 naviculare, being farther continued to the os cuneiforme inter- 

 num and medium ; besides it gives some tendinous filaments to 

 the OS calcis, os cuboides, and to the root of the metatarsal bone 

 that sustains the middle toe. 



Use. To extend the foot, and to turn the toes inwards. 



6. Flexor Longus Pollicis Pedis, 

 Arises, by an acute, tendinous, and fleshy beginning, from 

 the posterior part of the fibula, some way below its head, being 



