216 P. P. Slonimski and H. de Robichon-Szulmajster 



Table II 



Comparison of growth and mutation of control and 



INDUCED cultures 



Data from 12 independent experiments pooled together. 



* The mutation rate is defined here as the probability of a bud talien at random giving rise 

 to a mutant clone (of. Marcovlch, 1951). 



15 X 10 



Fig. 2. Frequency of respiration-deficient mutants 

 versus euflavine concentration. 



Other conditions as in Table III. 



