188 



THEORY OF EVOLUTION 



that is neither advantageous nor disadvanta- 

 geous, but indifferent, the chance that it may 

 become estabhshed in the race is extremely 

 small, although by good luck such a thing may 

 occur rarely. It makes no difference whether 

 the character in question is a dominant or a 



Kecenl 



Fleut9$eair eUPMAS 



Ishortchinj 

 VpperPliocene 



Comsr Pliocene TETRABELODON 

 Upper Miocene ishwtemngchinj 



Hiddh Miocetue TETRABELODON 

 LovfCT Miocene ^Imgehtnj 



' ' ^ utlo turope -Asia 



later Oligocentf 

 li^perEooene ■ 

 Mu/dteEheeKe 



■' PALAEOMASTOOQM 

 (fen^mipg thin) 



MOCRITHCKIUM 



Fig. 93. Evolution of elephant's skulls. (After Dendy.) 



