662 ENDOMIXIS 



different races or in the same race, synchronously or otherwise, thus adds 

 to the known repertoire of the versatile Paramecium. 



Conclusions 

 A synoptic view of the rapidly accumulating data on macronuclear 

 reorganization phenomena in the Ciliophora justifies, it is believed, the 

 statement that these processes include intrinsic reorganization (reor- 

 ganization bands, and so forth), cooperation of macronucleus and micro- 

 nucleus (endomixis), a new macronucleus of micronuclear origin (en- 

 domixis), and a new macronucleus of synkaryon origin (autogamy and 

 conjugation). These constitute a series of macronuclear metamorphoses 

 of increasing complexity, affording progressively greater possibilities for 

 the organism. 



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