POSTERIOE TIBIAL GROUP. 249 



PLANTARIS. 



{Soleus — Peroneo-calcaneus.) 

 (Pii. III. 39.) 



Situated on the postero-external part of the leg, to the out- 

 side of the gastrocnemius, this muscle is, in the horse, slender 

 find rudimentary, with a small, delicate tendon of insertion. 



Origin. — From the external part of the head of the fibula. 



Insertion. — Together with the tendon of the gastrocnemius to 

 the point of the calcaneum. 



Relation. — Externally with the fascia ; internally with the 

 gastrocnemius. 



Action. — It assists very slightly the gastrocnemius. 



FLEXOR PEDIS PEKFORATUS.* 



{Femoro-phalangeus. ) 



(Fig. 86 6.) 



Situated immediately underneath the gastrocnemius, this 

 muscle is in shape funicular, consisting of a strong fibrous cord, 

 with a slightly fleshy portion above, and arising from the supra- 

 <3ondyloid fossa ; the belly is succeeded by a strong tendon, 

 united to fascia, which is fixed to the inner surface and ridge of 

 the tibia and the summit of the calcaneum, being continuous 

 with the tibial fascia, and enclosing the entire tendo-Achillis. 

 The tendon, at first under that of the gastrocnemius, winds 

 round its inner side, and then surmounts it;. on reaching the 

 point of the calcaneum it forms a cap, giving slips of insertion to 

 the sides of that bone ; a large synovial bursa exists here, which 

 is one of the seats of the lesion termed capped hock. It now 

 descends posteriorly, and is disposed as is the corresponding 

 tendon in the anterior extremity, forming a synovial sheath and 

 ring for the perforans tendon, and finally bifurcating to become 

 attached to the sides of the os coronse. 



Relation. — Posteriorly with the gastrocnemius ; anteriorly 

 with the tibia, the popliteus, perforans, and accessorius muscles. 



* This muscle was formerly described under the name of gastrocnemius 

 intemus. The more appropriate one now in use is adopted here. 



