J. F. LOUTIT 



Table 2. Survivors of CBA mice, injected subcutaneously with 10« cells 

 leukaemia 151/1. treated after seven days with 1620 rad X-rays, and restored 

 with normal bone marrow injected intravenously 



scored, and the majority of the deaths were due to leukaemia either proven 

 or presumed. 



Table 4 shows the resuks from the second leukaemia, 151/2. Here our 

 experiences are more limited than with the former leukaemia, 151/1, and 

 all the results are included in the one table, whether the original route of 

 passage of the leukaemic cells was intravenous or subcutaneous. Successes were 



Table 3. Survivors of CBA mice, injected intravenously with 

 10" cells leukaemia 151/1, treated after seven days with 1620 rad 

 of X-rays and restored with normal bone marrow injected 



intravenously 



scored up to the eighth generation of passage of the leukaemia (Experiment 

 VIII). This leukaemia was not used subsequently for about a year, when it 

 was in its 59th generation of passage. Its rate of growth had then accelerated 

 so that most animals injected and kept as controls died within 7 to 

 10 days. 



Experiment IX was an attempt to extend the period of delay between the 

 intravenous injection of the leukaemic cells and the radiotherapy from 7 

 to 11 days. Leukaemia 151/1 was used and was then in its 14th generation. 



51 



