INTRODUCTION 13 



* Somatoplasm includes the body tissues, that is, the 

 bulk of the individual, which is fated in the course of 

 events to complete a life-cycle and die. Germplasm, 

 on the contrary, is the immortal fragment freighted ^ 

 with the power to duplicate the whole organism and 

 which, barring accident, is destined to live on and 

 give rise to new individuals. 



Germplasm thus carries potencies for developing both 

 germplasm and somatoplasm, while somatoplasm, ac- 

 cording to this conception, has only the power to repair 

 itself but not to reproduce a new individual. More- 

 over, germplasm is not freshly formed in each genera- 

 tion, neither does it arise anew when the individual i 

 reaches sexual maturity, as it appears to do, but it is 

 a continuous substance present from the beginning. 

 Although this theory of the contvnuity of the germ- 

 plasm has been actually demonstrated in comparatively 

 few instances, all the facts we know concerning the be- 

 havior of the germinal substance are consistent with it. 



The phrase "life everlasting" is not confined, there- 

 fore, to the vocabulary of the theologian, and poten- 

 tial immortality is more than a mystical hope of be- 

 lieving humanity. They are based upon demonstrable 

 biological facts, 



In many of the Protozoa the entire organism is 

 possibly comparable to germplasm, but in all forms of 

 life that are compounded of several cells the germplasm 

 is probably set aside early in the development of the 

 individual, and this remains undifferentiated, or in re- 

 serve, like a savings-bank account put by for a rainy 

 day, while the somatoplasm is expended in the imme- 



