208 NORBERT SCHCMMELFEDER 



creased density of the nuclear mass. Within the region damaged by irradia- 

 tion, Purkinje cells in a state of regression showed remarkable decrease or 

 loss of cytoplasmic RNA which was obviously secondary to cellular 

 regression. 



Acknowledgment 



The author wishes to acknowledge, with appreciation, the assistance 

 rendered in these studies by Dr. Bergeder and Dr. Ebschner, University of 

 Bonn, Germany, and the late Dr. E. Krogh, University of Aarhus, Denmark. 



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