186 Regulation of Size in Unicellular Organisms 



most completely in Colpidium colpoda (figure 63) by 

 Vieweger ('25). There was always a reduction in the 

 volume of the nuclei; the nuclei were reduced even 

 more than the cytoplasms, as indicated by the ratios 



Time of starvation in days 



Figure 63. Effect of total starvation at 20° C. in Colpidium colpoda. The 

 numerals /, II, III, represent three different cultures. (Data of Vieweger, 

 •25). 



plotted. This is just the opposite efTect from that ob- 

 served by Hertwig and Wallengren. Vieweger 

 showed that the reduction in nuclear size during the 

 ageing of mass cultures was much slower than that 

 during true starvation; yet qualitatively and relatively 

 it was the same. 



