MUSCLES OF THE POSTERIOR LIMBS. 



375 



2. External Kkgion (Fig. 206). 



This region is only composed of two muscles : the long and short peroneus. 



The first, which does not exist in Solipeds, is a penniform muscle attached to the upper 

 third of the fibula, the external tuberosity of the tibia, and the internal face of the tibial 

 aponeurosis, by the superior extremities of its muscular fibres. The flat tendon which termi- 

 nates it is fixed to the outer portion of the base of the first metatarsal. 



The second corresponds to the lateral extensor of the phalanges of the Horse, and is found 



Fig. 206. 



Fi^. 207. 



,5 



SUPERFICIAL POSTERIOR MUSCLES OF THE 

 HUMAN LEG. 



1, Biceps forming outer ham-string ; 2, ten- 

 dons forming ianer ham-string ; 3, popli- 

 teal space ; 4, gastrocnemius ; 5, 5, soleus ; 

 6, tendo-Achilles ; 7, posterior tuberosity 

 of OS calcis ; 8, tendons of peroneus longus 

 and brevis passing behind the outer ankle ; 

 9, tendons of tibialis posticus and flexor 

 longus digitorum passing into the foot 

 behind the inner ankle. 



OF THE HUMAN LEG (ANTERIOR 

 TIBIAL REGION). 



1, Quadriceps extensor inserted into the pa- 

 tella (the figure is on the tendon of the 

 rectus, the vastus internus and externus 

 being on each side) ; 2, subcutaneous sur- 

 face of the tibia ; 3, tibialis anticus ; 4, 

 extensor longus digitorum ; 5, extensor 

 proprius pollicis ; 6, peroneus tertius ; 7, 

 peroneus longus; 8, peroneus brevis; 9, 9, 

 borders of the soleus muscle; 10, part of 

 the inner belly of the gastrocnemius ; 11, 

 extensor brevis digitorum (the tendon in 

 front of the cipher is that of the peroneus 

 tertius ; that behind it, the peroneus brevis). 



in all animals. It is penniform, and is attached above, by its fleshy fibres, to the lower two- 

 thirds of the external face of the fibula ; below, by its tendon, to the upper extremity of the 

 fifth metatarsal. 



These two muscles determine very complicated movements in the region of the foot 



3. Posterior Region (Fig. 207). 

 The posterior tibial muscles form two layers : a superficial and a deep. 



