1874.] 



MYOLOGY OF PHRYNOSOMA. 



Sdeus (fig. 6, So.), the most superficial muscle on the back of 

 the leg, arises from the posterior surface of the head of the tibia ; the 

 semitendinosus is inserted close to its origin, and gives off a tendon 

 which borders its inner edge. The muscle in question terminates in 

 a broad thin membranous tendon which is lost over the tarsus, but 

 is more particularly attached to the cuboid and outer side of the 

 metatarsal bone of the fifth digit ; this appears to be the tibial head 

 of the soleus, the gastrocnemius not being represented. This muscle 



Fig. 6. 



Arrangement of the tendons surrounding the knee-joint. X o. 



is not present in L. belli, but is met with in P. japonicum, where it 

 was named extensor tarsi, and where its origin accords more with one 

 head of the soleus of anthropotomy in arising from the middle of the 

 shaft instead of from the head of the tibia. 



Flexor perforatus digitorum (fig. 5, F.S.) arises from the outer 

 condyle of the femur. It ends in two bellies, one of which joins the 

 deep flexor ; the other expands into a broad tendon, which is attached 

 on one side of the tarsus to the cuboid, and on the other to the 

 tibial side of the astragalo-calcaneus. From this broad tendon two 

 muscles continue on to the sole : these are perforated for the passage 

 of the perforans tendon, one being inserted on each side of the base 

 of the first phalanx of the first digit, the other on each side of the 

 base of the first phalanx of the second digit. The third digit also has 

 a perforatus ; but this arises independently from the cuboid, and is 

 inserted like the other two : the fourth and the fifth digits have no 

 perforatus. 



Peronceus primus (fig. 5, P.P.), like that of L. belli, arises from 

 the external condyle of the femur by a flat but narrow tendon, 

 expands in the leg into an elongated muscular mass, and terminates 

 in a long thin tendon which is inserted into the cuboid. 



