PARAMOECIUM POSSESSING EXTRA VACUOLES 



315 



ber of vacuoles in the daughter cells was recorded and the ani- 

 mals were separated and again allowed to divide when the opera- 

 tion was repeated. The results of these experiments are shown 

 in the charts 8, 9 and 10. The last generations on chart 8 and 9 

 show practically 50 per cent of twos and threes. The same gen- 

 eration on chart 10 shows a much higher percentage of twos. 

 A study of these charts will, I think, convince the reader that 



O 



Chart 8 This figure illustrates the mode of inheritance for four generations 

 from a two-vacuoled progenitor. The heavy figures indicate the number of 

 vacuoles for any descendant. 



the number of vacuoles any one mdividual may possess is no 

 indication of its potentialities — that the fewer-vacuoled para- 

 moecia may give rise to animals with more vacuoles and vice 

 versa. The last statement was demonstrated by starting cul- 

 tures with several of the animals possessing different numbers of 

 vacuoles from the fourth generation of these lines. After the 

 lines had multiplied considerably examination showed the per- 

 centages to be in no way different from those given throughout 

 this paper. In the case of experiments such as these the two- 



