54 The mnemic theory presupposes 



But what exactly is this continuity be- 

 tween body and germ, and how are new 

 acquisitions passed on? The continuity is 

 what it always was, the continuity of mem- 

 bership in a commonwealth, where the whole 

 is for the parts and the parts for the whole ^ ; 

 where all are more or less en rapport. The 

 key to all this is to be found, I believe, in 

 social intercourse, not in physical trans- 

 mission. Unhappily however — as it seems 

 to me — most of those who uphold the 

 mnemic theory of heredity seem to hanker 

 unduly after a physical explanation of the 

 modus operandi, Hering and Haeckel 

 talked of peculiar vibrations : if they were 

 writing to-day they would probably refer to 

 wireless telegraphy, as Professor Dendy has 



1 A Protozoan, we must remember, though unicellular, is far 

 from simple, and an absolutely simple form of life is beyond 

 our ken. 



