2 



1 8 



1 6 



14 



1 2 



1 



,s 



6 



4 



2 







PO\TASSIUM PHOSPHATE 



I MAR I AFR I MAY [ JUNE 

 J 1 h 2 13 14 I 1 5 16 1 7 I 1 8 I 9 2 I 21 22 23 



JULY 

 24 25 



Diagram IV 

 Histories of treatment with beef, pancreas and potassium phosphate during a period of four and one- 

 half months, together with the history of the control culture during the same period. Rate of division 

 averaged for ten-day periods. In the beef history the broken line indicates the vitality of the individuals 

 that were not treated again at the beginning of the i6th period. 



