68 RHODA ERDMANN AND LORANDE L. WOODRT'FF 



process either by Hertwig, Kasanzeff or Popoff in their mass 

 cultures. However, Hertwig's suggestion that "Wooch-uft" und 

 Erdmann konnten somit die Stadien als Beweise fiii- eine vor- 

 ausgegangene Parthenogenese in Anspruchnehmen " is a partially 

 right prediction, provided one substitutes for 'parthenogenesis,' 

 reorganization process — endoniixis! Since Kasanzeff did not 

 find stages of the ascending ])hase, that is the formation of the 

 macronuclear anlagen, in Paramaeciuni caudatuni mass cultures, 

 Hertwig still believes that the described phenomena are depres- 

 sion conditions and not stages of the reorganization process, 

 though he himself described in Paramaeciuni aurelia isolated 

 stages of a process which he called 'parthenogenesis. '- 



We wish to emphasize that in a mass culture it is impossible 

 to know the ancestry of the individual cell. It is clear that 

 from a mass culture so-called depression stages may be either 

 animals which are about to begin the reorganization process, or 

 animals which have just undergone conjugation, or abnormal ani- 

 mals due to some exigencies of the environment. From material of 

 this sort, in view of the fact that the reorganization was not 

 known previous to our work, there has been drawn into the litera- 

 ture on infusorian life histories the long series of atypical 

 animals as evidence of depression. However, by pedigreed 

 culture methods we have resolved this heterogeneous material 

 into its component parts and have shown for both Paramaecium 

 aurelia and Paramaecium caudatum that many of the so-called 

 depression phases are normal stages in a complex reorganization 

 phenomenon. 



B. Climax. Culture Y of Paramaecium caudatum we had 

 under observation from February 18, 1914, to June 9, 1914, and 



^ We have not called the reorganization proces.s 'parthenogenesis' and have 

 not introduced even our new term 'endoniixis' in our preliminary papers ('14, I 

 and '14, II) because we wished to wait until our complete data was presented 

 ('14, III) so that they could be discussed in their entirety. However, in our brief 

 paper ('14, II) ah error is present on page 495, owing to the fact that the printer 

 misunderstood our directions and that we were unable to revise the proof on ac- 

 count of the war. The sentence "Diese Parthenogenese hier ist ein Sexualakt." 

 is a remnant of a paragraph which appeared in the manuscript Ijut was entirelj' 

 deleted in the proof, but the printer in some way left this one isolated sentence 

 for the complete paragraph! 



