80 THE CONTROL OF LIFE 



not physiological conclusions relating to individuals. 

 But of course they sum up a multitude of individual 

 physiological facts. 



(6) They do not apply to lineages where there has 

 been close and consistent selection, e.g. in the range of 

 permissible marriages. 



(c) They certainly do not apply to the inheritance 

 of Mendelian unit-characters. Not that there is any 

 opposition between Galtonian and Mendelian laws oi 

 inheritance ; they are not antithetic, but complemen- 

 tary, approaching the problem from different sides. 



{d) It is difficult to believe that the laws are quite 

 sound as laws of inheritance, since they do not seem 

 to have taken sufficient account of the important fact 

 that resemblances between relations are often in part 

 due to similar nurture, and are not wholly due to similar 

 hereditary nature. 



To the statisticians or biometricians we owe a demon- 

 stration of the heritability of subtle constitutional 

 qualities like fecundity and longevity, and evidence 

 that clearly defined mental and moral qualities may 

 be handed on to, and distributed among, the offspring, 

 just in the same way as bodily characters. In this 

 connection too we must recognise the assimilative potency 

 of similar nurture, a subject to which we must return 

 in the next chapter. 



Looking Forward 

 The history of domestication and cultivation shows 

 that great results may be achieved when Nature and 



