370 THE ANATOMY OF VEETEBEATED ANIMALS. 



plialanx of the second digit. K pronator teres is inserted 

 into the lower half of the radius. The flexor perforatus has 

 only two tendons, which go to the third and fourth digits. 

 The flexor perforans sends two large tendons to the third 

 and fourth, and two small ones to the second and fifth 

 digits. There is a large interosseus muscle on the radial 

 side of the third digit, and another on the ulnar side of the 

 fourth ; but the interossei of the interspace between these 

 digits are represented only by fibrous tissue. The second 

 and fifth digits have each two interossei. There is no 

 soleus. The strong and fleshy plantaris arises from the 

 outer condyle, beneath the gastrocnemius ; and, inclosed 

 between the two heads of the latter, passes to the inner 

 side of the tendo Achillis ; its tendon curves round this 

 tendon, passes over the end of the calcaneum as over a 

 pulley, enters the sole, and finally divides into the two 

 perforated tendons of the third and fourth digits. The 

 inner and oiiter digits of the pes, like those of the manus, 

 have no perforated tendons. 



A lai'ge and fleshy flexor hallucis longus arises from the 

 fibula and the interosseous ligament, and its broad tendon 

 passes into the sole and coalesces with the tendon of the 

 smaller flexor longus digitorum. The conjoined tendons 

 divide into four slips — two large, median, and two small, 

 inner and outer. These go to the distal phalanges and 

 sesamoids of the respective digits. 



The tibialis posticus is absent, but there is a small tibialis 

 anticus. 



A very complicated muscle represents the extensor longus 

 digitorum and the peronceus tertius. It arises by (a) a strong 

 round tendon from the outer condyle of the femur, just in 

 front of the external lateral ligament. Prom this tendon 

 proceed two fleshy bellies, one of which supplies tendons to 

 the third, fourth, and fifth digits, while the other ends in a 

 broad band of tendinous fibres, which is inserted into the 

 third metatarsal and the ectocuneiform. Into this band is 

 inserted {h) the second fleshy head which arises from the 

 upper part of the tibia ; and it is traversed by the tendon 



