202 Dr. Bashford and Messrs. Murray and Bo wen. [May 30, 



The data obtained from these four experiments, viz. : — 





The day of propagation. 

 AbscisBa. 



The percentage of success. 

 Ordinate. 



Name of experiment. 







Per cent. 





1 



739 



55 



46 C. 



2 



751 



47 



46 F. 



3 



753 



66 



46 G-. 



4 



768 



32 



46 K. 



suffice to determine four points, indicated on the chart by the numbers and 

 letters in the third column. 



The four fragments of the parent tumour from which the four tumours 

 used for the above experiments (1, 2, 3 and 4) developed were implanted 

 along with 51 other fragments into 55 mice on the 723rd day of propaga- 

 tion, the experiment being labelled 45 C ; 23 mice were killed in the 

 first 10 days after transplantation for microscopical examination of the 

 site of implantation ; 17 tumours developed in the remaining 32 mice, 

 i.e., 53 per cent, of the implantations were successful. These two numbers, 

 723 as abscissa marking the date of transplantation, and 53 as ordinate 

 marking the percentage of success of implantations, together fix a fifth 

 point labelled on the chart 45 C. The four points previously obtained 

 represent the results of transplantation experiments on four of these 

 17 tumours, and to indicate this relation they are each connected with the 

 point labelled 45 C by a straight line. 



In the same way a point has been obtained for the parent tumour of 45 C 

 indicated on the chart as 44 D, and similarly for the transplantations 

 antecedent to 44 D and subsequent to 46 G as shown in the larger charts. 



The following condensed summary of a number of consecutive experi- 

 ments will make clear the nature of the results to be recorded in this 

 manner. A tumour of the 39th Transplantation, transplanted into 37 

 animals, gave tumours in 3 of the 20 animals remaining alive after 10 days 

 (15 per cent.), Transplantation 40, Series I, or shortly 40 I. Of these mice 

 one developed two large tumours weighing together 7'5 grammes in 49 days, 

 when the animal was killed and the tumour transplanted into 24 mice. 

 Tumours developed in 4 of the 20 animals which survived the first 

 10 days after transplantation (20 per cent.), 41 P ; 14 days afterwards 

 one of these tumours weighing 1*3 grammes was transplanted in 66 mice ; 

 tumours developed in 7 of the 31 survivors (23 per cent.), 42 L. Of 

 these a tumour, having attained a weight of 4 grammes after 42 days' 

 growth, was transplanted into 45 mice. Tumours developed in 13 of the 



