Rejuvenescence as a Result of Conjugation 89 



physical difference exists between the two unicellular organisms 

 which unite in conjugation and a difference of the same nature as 

 that expressed morphologically in the case of Adelea ovata, where 

 the male gamete does not fuse with the female but dies after 

 delivering one of its four pronuclei. 



Baltimore 

 August, 1906 



