240 



ME. W. P. PTCEAFT ON THE MOEPHOLOGT AND 



Fig. 5. 

 A. 



B. 



i>.e. 



conjoined flexors digitorum is highly suggestive of a walking or climbing animal. 

 It seems to be conceivable that the Ostrich branched off" from the avian stem before 

 the power of flight was perfectly established. 



" The biceps oi Struthio arises from tlie siyina coracoidea and is inserted on to the radius 

 and ulna and the membrane between them. The extensor metncarpi radialis is single. 

 The ectej)icondi/lo-ulnaris is absent or fused with the extensor metaccirjri ulnaris. The 

 extensor digitorum communis supplies only the index. The two ^^''"onators form only 

 one muscle. The fiexor digitorum suhliinis and jjrofundus arise by a single head 

 from the flexor condyle of the humerus. The two muscles immediately divide; the 

 upper part (:=sublimis) ends in two tendons, of which one is inserted on to (the) 



