270 L- H. Gray 



disturbances induced at higher dose levels as a result of either 

 nuclear or cytoplasmic damage, but these may be quite 

 irrelevant to the metabolic pathways leading to loss of repro- 

 ductive integrity at low dose levels. 



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DISCUSSION 



Latarjet: I should like to say a few words about this problem of 

 ploidy and survival curves. The main fact, as Dr. Gray mentioned, is 

 that the number of hits which comes out of the survival curve fits with 



