VIII.] 



THE MUSCLES, 



357 



still distinguishable, even in Tailed-Batrachians, as in Mcno- 

 pojna and Menobranchus. 



The tibialis posticus may be entirely absent, even in man's 

 class, as in the Rabbit and Tapir. It may be very stron^ 

 and inserted into the astragalus, as in the Echidna, or run 

 on to the ento-cuneiforme, as in Lemur. The muscle may 

 be very greatly developed, as in the Beaver and Wombat. It 

 is constant, as not only in Reptiles (e.g. Iguana and 

 Chameleo], but even in the Frog it exists (inserted into the 

 astragalus), though it does not seem distinct in Tailed- 

 Batrachians. 



FIG 318. TENDONS AND MUSCLES OF EXTENSOR ASPECT OF FOOT OF EAr;i K 

 (A quilafnc osa). 



i, tibialis anticus ; 2 and ?,peronei ; 4, tendon of extensor longus digitorum pedis ; 

 5 and 6, extensor hallucis ; 7 and 8, tendons going to third and fourth digits 

 respectively. 



(After A. Milne- Edwards.} 



27. The MUSCLES OF THE FOOT of man possess of course, 

 like its skeleton, special characters in harmony with the 

 peculiar function of that organ as the sole support and agent 

 of progression of an erect and relatively large and ponderous 

 body. These muscles, like those of the hand, can for the 

 most part be profitably compared only with those of man's 



