CHAPTER XVI 



ARE INDIVIDUALLY ACQUIRED CHARACTERS INHERITED ? 



The question which forms the title of this chapter 

 will not, perhaps, strike the general reader who is un- 

 acquainted with recent developments of biology as being 

 of much importance, or as having any special interest for 

 the world at large. Yet it really involves considerations 

 hardly less far-reaching than evolution itself, since the 

 correct answer to it must depend upon, and be a logical 

 consequence of a true theory of heredity. If, then, we 

 can arrive at this correct answer, either by means of 

 observation of natural phenomena or by experiments with 

 living organisms, we shall possess a criterion by w^hich to 

 judge between rival theories : Avhile the answer itself will 

 be found to have a direct bearing of a very important 

 kind on possibilities and methods of human improve- 

 ment.^ 



Theories of Galton and Weismann, 



Up to about ten years ago the answer to the question 

 would have been almost unanimously in the affirmative. 

 Darwin accepted the inheritance of such characters as an 

 undoubted fact, though he did not attach much import- 

 ance to it as an agent in evolution ; and his theory of 

 pangenesis was an attempt to explain the phenomena of 

 heredity in accordance with it. Mr. Francis Galton made 



1 This aspect of the question is discussed in a later chapter. 



