Death and Dissolution of the Organism 369 



nuals, die after fructification. Metchnikoff quotes 

 from a letter by de Vries that this author prolonged 

 the life of CEnotheras by cutting the flowers before 

 fertilization. 



Under ordinary conditions the stem dies after producing 

 from forty to fifty flowers, but if cutting be practised new 

 flowers are produced until the winter cold intervenes. By 

 cutting the stem sufficiently early the plants are induced 

 to develop new buds at the base and these buds survive 

 winter and resume growth in the following spring. 



Metchnikoff suggests that it is a poison formed in the 

 plant (in connection with fructification?) which kills 

 the annuals, while it is not formed or is less harmful 

 in the perennials. He compares the situation to the 

 death of the lactic acid bacilli if the lactic acid is allowed 

 to accumulate. This hypothesis is certainly worthy 

 of consideration, and it is quite possible that in addi- 

 tion to structural shortcomings poisons formed by 

 certain organs of the body as well as poisons formed 

 by bacteria account for the phenomenon of death in 

 metazoa. 



34 



