108 THE NATURE OF LIFE 



probably acts directly upon the germ 

 cell. We are particularly interested in 

 knowing whether it is possible to produce 

 inherited effects indirectly by inducing 

 changes in the body cells which then re- 

 act in such a way as to alter the germ cell. 

 If this were possible we might expect that 

 the normal activity of the body cells 

 might also affect the germ cells and that 

 in this way the inheritance of so-called 

 acquired characters could be brought 

 about. 



We are not yet able to answer this 

 question decisively. Some recent exper- 

 iments of Griffith, Bentley and Detlefsen 

 are of interest in this connection. White 

 rats were kept for several months in 

 cages which revolved continuously at a 

 rate of 60, 90 or 120 revolutions per min- 

 ute. Such rats when returned to normal 

 conditions showed distiu'bances of the 

 equilibrating apparatus as evidenced by 

 modified muscular and ocular movements 

 and twisting of the head and neck. These 

 disturbances are inherited and it would 



