SERIAL ORGANIC EVOLUTION 247 



call both molecular combinations " amoebae " would 

 be a misuse of nomenclature. 



Ray Lankester admits : " We have no reason to 

 suppose that the offspring of the beetle could in 

 the course of any number of generations present 

 variations on which selection could operate so as 

 to eventually produce a mammalian vertebrate ; 

 or that, in fact, the general result of the pro- 

 cess of selection of favourable variations in the 

 past has not been ah initio limited by the definite 

 and restricted possibilities characteristic of the 

 living substance of the parental organisms of each 

 divergent line or branch of the pedigree." 



Good ! but why begin at beetles } Why not 

 go a step farther back and say that we have no 

 reason to suppose that the offspring of the amoeba 

 could in the course of any number of generations 

 present variations on which selection could operate 

 so as to eventually produce a mammalian verte- 

 brate ? Why not also admit that we have no 

 reason to suppose that the twins of an amoeba 

 could present such different variations and be 

 exposed to such different environments that in the 

 course of a million years one should become a 

 beetle and the other a man } 



It is all very well to limit the possibilities of 

 each branch of the biological tree by the possi- 

 bilities of its progenitor, but how about the stem r 



