G. ROY LANE 



Table I. — Frequency of breaks and interchanges after treatment with di-{2 : 3-epoxypropyl) ether, 

 MI2,000 for 20 minutes, and Mj2,000 for 30 minutes 



* 50 cells from each of 2 slides 



30 m\n. treatment 

 20 mm. treatment 



Time m tergal h. 



Figure 1. Frequency of breaks and interchanges after treatment with di{2 : 3- 

 epoxypropyl) ether M {2, 000 for 20 minutes and MI2,000for 30 minutes 



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