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DISCUSSION 



Hollaender: The work of Dr. Gaulden which Dr. Howard referred to 

 was done on the grasshopper neuroblast. Dr. Gaulden has shown that 

 one can counteract the effects of radiation on the rate of mitosis by 

 placing the neuroblast in a hypertonic salt solution immediately after 

 irradiation (see p. 303). 



Van Bekkum : How long does the irradiation take ? 



Hollaender : It takes about 1 minute. 



Alexander: Could you tell us the experimental details of this treat- 

 ment with hypertonic salt? 



Hollaender: It contains 1 -2 times the concentrations of inorganic salts 

 in the medium isotonic to the grasshopper neuroblast. In other words, 

 it is only slightly hypertonic to the cells. 



Alexander: Could you tell us the time of immersion in the more con- 

 centrated salt solution? 



Hollaender: Throughout observations (264 minutes). 



