ERIK ZEUTHEN AND OTTO SCHERBAUM 



By this time it will be painfully clear that we are not in the position to look back 

 and point out exactly where we were right and where wrong in our working hypo- 

 theses. The essential thing is that we got some of the results (Scherbaum and Zeuthen, 

 J 954) we were hoping for. In the synchronized cultures all those three phases are 

 present into which we divided the cell cycle in normal Tetrahymena cells; only their 

 quantitative relationships are somewhat changed. For bacteria, Hotchkiss (1954) 

 has quite independently and almost at the same time worked out a method of syn- 

 chronization based on very similar arguments and using temperature shifts. We have 

 not made further reference to this work because this will be done by Dr. Maaloe 

 (Maaloe and Lark, 1954), who is going to speak next. 



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