546 



WALDO SHUMWAY 



To test this point still further another experiment was per- 

 formed in which a line was maintained on boiled thyroid prepared 

 by boiling the usual thyroid suspension for ten minutes and 

 adding boiled water to supply that lost by evaporation. The 

 control line and the thyroid line of Experiment B 3 were contin- 

 ued during this experiment until the life cycle of the B' line came 

 to an end, the thyroid line after sixty days of treatment dying out 

 at the same time. The di^asion rates by five day periods are 

 shown in table 17. 



TABLE 18 

 Race B" . Experiment 6. Daily division rate averaged by five day periods 



