.«,.. DEATH. 441 



comparison of the constitution with the effects of the different poisons 

 which act on protoplasm. This is already leading towards a know- 

 ledge of the actual occurrences in a living cell, and it will no doubt 

 get more and more clear that the events which cause protoplasmic death 

 are simple interferences with the cell economy arising from internal 

 or external accidents. As in bacteriology, the idea that the fatal 

 influence of these parasitic organisms is due to a struggle between 

 life and life, has been displaced by the idea that it is due to the direct 

 action of a poison accidentally discharged by the parasites, so the 

 causes of protoplasmic death will be attributed less and less to any 

 inherent mortality in protoplasm. There seems no good evidence 

 that protoplasm in suitable conditions, with sufficient food, should 

 ever die, just as there is no reason that a flame, with a constant 

 supply of fuel, and removed from violent draughts, should not burn 

 from the beginning of time to the end of time. But the more com- 

 plex flame of life is disturbed by many agencies, and these agencies 

 cause protoplasmic death. In the metazoa, where each cell may suffer 

 by the accidents of every cell, a new danger, the danger which is here 

 called somatic death, is so urgent as to be fate rather than accident. 



P. Chalmers Mitchell. 



