An Introduction to a Biology 



a difference, he is not denying the validity of the Law of 

 Ancestral Inheritance but the Law of Diminishing Individual 

 Contribution. At least, I think this is the correct attitude. 



And I cannot bring myself to agree with Bateson when 

 he says that facts once describable by Mendel's Law are 

 permanently removed from the operation [sic] of the Law 

 of Ancestral Inheritance, unless all that he means by this 

 statement is that when we have gained this deeper know- 

 ledge of certain hereditary phenomena their further treat- 

 ment by the method of the correlation table will not increase 

 our knowledge of them. I should like to think that this is 

 all he means ;J but his writings prevent me, for he imputes 

 to upholders of Pearson's Law belief in the Law of Contri- 

 bution ; l yet on the next page he shows that he has not 

 confused the two, by saying that the Law of Ancestral Heredity 

 " does not directly attempt to give any account of the distribution 

 of the heritage among the gametes of any one individual." I 

 do not know whether Bateson still holds that Mendel's Law 

 is antagonistic to the Law of Ancestral Inheritance as well 

 as to the Law of Contribution. If he does, I do not under- 

 stand on what grounds. Pearson has investigated the re- 

 lation between the two, and concludes " that in the theory 

 of the pure gamete there is nothing in essential opposition 

 to the broad features of linear regression, skew distribution, 

 the geometric law of ancestral correlation, etc., of the bio- 

 metric description of inheritance in populations." 2 And 

 no flaws in the argument of my paper on the supposed an- 

 tagonism of Mendelian to biometric theories have been 

 pointed out to me ; in fact, Correns 3 and Giard 4 have 

 expressed their agreement with it. 



I feel most strongly that so long as we confuse physio- 

 logical with statistical Laws of heredity we are wandering 

 in the dark : we cannot know in what direction our studies 

 are leading us, whether we are establishing correlations 



1 Bateson, :02, p. 21, second half. 2 Pearson, :03&, p. 86. 



3 Correns, :05, p. 43. * Giard, :0o, p. 22. 



