218 



Arne Forssberg 



conclusion by the fact that the specific activity curves of RNA 

 and DNA agree in the series labelled with ^^C-glycine and ^^C- 

 adenine. In the latter case no marking of the proteins or the 

 tissues of the host takes place. 



The ratio of the specific activities of RNA : DNA is compara- 

 tively constant during the whole period of observation of the 

 transferred inoculates, and the mean value of • 72 is seemingly 

 independent of whether adenine or glycine is used as precursor 

 (Table I). 



Table I 



Ratios of the Specific Activities of RNA : DNA in the Inoculum and at 



Various Times after Inoculation 



Furthermore, in the inoculum sample at zero day the specific 

 activity ratio is 1, and earlier still, i.e. shortly after injection 

 of the labelled compound, values ranging from 1 • 5-4 are 

 found. 



This decrease in the RNA: DNA specific activity ratio and 

 the eventual attainment of a steady state calls to mind the 

 similar results of Ledoux and Revell which, however, were 

 arrived at from determinations of the total amounts per cell 

 in the related Landschiitz tumour. Assuming that similar 

 conditions prevail in the Ehrlich cell, the initial loss in RNA 



i 



