FREQUENCY OF SPONTANEOUS BACTERIOPHAGE MUTANTS 



32 64 X 



FIG. 1. The distribution of mutant clones, x = number of mutants in a clone. 

 Y = number of clones with x or more mutants. X : r mutants. C : w mutants. 

 • : r and w mutants. The solid lines represent the theoretical distributions, with 

 slope —1. 



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