HEREDITY AND ENVIRONMENT 201 



it would be to argue that the possession of a fleet 

 is determined by the " nature " of an embryonic tribe 

 which has not yet seen the sea. Environment and func- 

 tion cannot be ignored. A fleet does not grow up by 

 minute advantageous " spontaneous " variations. It is an 

 acquired tool, and itself determines further historic evolu- 

 tion. The " constant " in germ-plasm is the nature of 

 protoplasm : its infinite variability, as shown in all forms 

 of life, is a variability which is further and further con- 

 stricted into more and more definite lines by definite 

 constructions, until at last in a static environment stasis 

 is reached. Yet the discovery of another tool, a new 

 means of short-circuiting labour, may again set the static 

 organism upon a voyage of discovery among the potentia- 

 lities of life. With change of function, which should in- 

 clude the phenomena of regeneration and reduction, comes 

 morphallaxis. Without it there is none. Death itself is an 

 acquired characteristic. If the organism were not perpetu- 

 ally preyed on by other organisms, which by parasitism and 

 poisoning divert or hinder energy, inhibit, or over-activate, 

 metabolism through the induction of changes in the endo- 

 crines, and destroy tissue functions generally, it is con- 

 ceivable that such a characteristic as death might be 

 lost, and that any body, however highly developed, might 

 resume the long-abandoned characteristics of unicellular 

 organisms, and again become practically immortal. 



REFERENCES. 



Bayliss and Starling. — " Mechanism of Pancreatic Secre- 

 tion," Jottrn. Physiol., London, p. 28. 



Belogolovy, G. A. — " Nonvcanx Memoires," Soc. Imp. 

 Naiuralistcs de Moscow, 1916. 



Butler, Samuel. — " Unconscious Memory." 



