14 HEREDITY 



structure of organised and unified knowledge of whicli 

 the theory of evolution is the architectonic principle. 



In discussing the problems of heredity, it is 

 necessary very fully to consider certain changes 

 which are found to occur in all individual organisms, 

 animal and vegetable. These changes are the result 

 of the individual experience — the result of the series 

 of relations between the individual and the environ- 

 ment. Considered from this point of view, they 

 might be called adaptations, since they may all be 

 included under the products of adaptation. Other 

 names may be employed. These changes necessarily 

 cause each individual to vary from the type of 

 its species, from even its immediate ancestors, its 

 brothers and its sisters. Hence they might be called 

 variations. But if we used this term it would be 

 necessary to employ qualifying adjectives, so as to 

 point the distinction between these variations and 

 those which depend upon the innate or germinal 

 characters of the individual. These last might be 

 termed blastogenic variations, whilst the changes 

 produced in the individual body by its converse with 

 its surroundings might be called somatogenic. But 

 I do not propose to employ these terms at all, my 

 reason being that they do not adequately emphasise 

 the cardinal and all-important distinction (as we 

 now see it) between innate and acquired characters. 

 Hence the term variation will be strictly confined 

 hereafter to those changes from the specific type 

 which are innate and which must now be regarded 

 as really not distinct in origin from the characters 

 which are obviously derived from the parent. Those 



