No. 578] 



CYCLES AND RHYTHMS 



67 



dence is further adduced to show that similar processes 

 occur in Paramecium caudaium. 



While there is little to criticize in regard to the facts as 

 described for this, remarkable process, there is room for 

 difference of opinion in regard to the conclusions which 

 Woodruff and Erdmann draw from them. In addition 

 to what Hertwig has already written about this work, I 

 would call attention particularly to their conclusions con- 

 cerning endomixis, parthenogenesis, conjugating and non- 

 conjugating lines, the life cycle, and the potential immor- 

 tality of Paramecium. 



In regard to endomixis the authors state : 

 Since the process results in the dissemination of the material from the 

 old macronucleus and the so-called reduction micronuclei in the cell, it 

 gives the opportunity for a rearrangement of the molecular constitu- 

 tion of the cell. This involves a more profound intermingling of 

 nuclear and cytoplasmic substances than is possible during the typical 

 vegetative life of the cell. Since this intermingling occurs within a 

 cell we term this reorganization process endomixis. Endomixis is fol- 



Further on they add : 



We would thcrofnrc |»ut emphasis on molecular rearrangement as the 

 result common both to endomixis and to conjugation. 5 



Nearly forty years ago Engelmann interpreted conju- 

 gation in much the same way as a process of reorganiza- 

 tion of the cell : 



In several places in the same publication Engelmann 

 speaks of physical and chemical changes as accompanying 



* Woodruff and Erdmann, "A Normal Periodic Keorganization Process 

 without Cell Fusion in Paramecium," Jour. Exp. Zool., Vol. 17, No. 4, 

 1914, p. 491. The italics are in the original. 



8 Ibid, p. 491. 



«"Ueber Entwickelung und Fortflanzung 'von Infusorien," Morph. 



