Il6 THE CYTOLOGY AND LIFE-HISTORY OF BACTERIA 



Sexual fusion may also occur in the secondary nuclear phase in eubacteria, 

 and has been reported to take place at the edges of Proteus swarms. 



Cytological evidence of the nuclear cycle indicates that the vegetative 

 form is haploid, and that fusion is immediately followed at a varying interval 

 of time by a reduction process with the elimination of one or more daughter 

 nuclei. The gametes are homothallic. Fusion is occasionally sexual but more 

 frequently autogamous. These conclusions are confirmed bv genetical 

 evidence. 



The complex method ot vegetative reproduction is also probably sexual. 

 It is analogous to the formation and fragmentation of a symplasm. 



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