THE ORIGIN OF VERTEBRATED ANIMALS 195 



two aortic arches in some cases, and in the occasional 

 development of the muscles of the ear. 



Like all higher animals man is primitive in some 

 respects, for he is pentadactyl and plantigrade (i.e., 

 five-fingered and walks on the flat of the foot), and 

 retains the power of supination and pronation of the 

 fore-arm ; these conditions being more primitive 

 than those met with in other Vertebrates which are 

 on the whole of lower organisation. 



In fact, unless man wishes to continue going about 

 the world stamped with living and palpable proof of 

 his kinship with lower animals, he had better stop 

 up his ears, or, still better, cut them off altogether ; 

 Ifor so long as he bears at the side of his head those 

 jtell-tale flaps with their aborted and rudimentary 

 Imuscles, so long as he hears by means of that slit, 

 once a gill-cleft, now by change of function become 

 an accessory organ of hearing, so long does he carry 

 about in sight of all men sure proof of his relation- 

 ship with lower, even with water-breathing animals. 



Yet one can hardly recommend the operation, for 

 if you were to remove one by one the various parts 

 of your body which proclaim this kinship, you would 

 Jget rid in succession of skin, muscles, nerves, bones, 

 &c, and all that would be left in the end as man's 

 special and peculiar possessions would be: (1) cer- 

 tain parts of his brain, and these only doubtfully; 

 (2) the extensor primi intemodii pollicis muscle, 

 which straightens the first joint of the thumb ; (3) the 

 peroneus tertius, a small muscle in front of the lower 

 part of the leg and ankle, inserted into the base of 

 the little toe ; (4) certain portions of other muscles. 



