212 Dr. Bashford and Messrs. Murray and Bowen. [May 30, 



Transplanted into 40 normal young mice, of which 10 died within 10 days ; 

 in the remainder 18 tumours developed as under : — 



Number of 

 mouse. 



Day of 

 growth. 



Weight of 

 mouse. 



Weight of 

 tumour. 



Naked-eye appearance. 







grammes. 



grammes. 



No necrosis. 



1 



10 



11 -8 



0-3 



2 



11 



14 -35 



0-9 



33 



3 



14 



12 75 



0-8 



Slight diffuse necrosis. 



4 



14 



8-3 



1 -1 



Very slight necrosis. 



5 



15 



9-2 



13 



Diffuse necrosis. 



6 



16 



6-95 



1 -16 



No necrosis. 



7 



17 



14 -6 



0-65 



Central necrosis. 



8 



17 



12 -2 



0-2 



Slight difluse necrosis. 



9 



17 



11 -85 



2-15 



Diffuse necrosis. 



10 



17 



16 -7 



1 -o 



No necrosis. 



11 



17 



14 -8 



0-7 



Diffuse necrosis. 



12 



17 



13 -6 



2 -25 



33 



Slight central necrosis. 



13 



]7 



13 -7 



0-8 



14 



17 



14 -2 



1 -85 



Diffuse necrosis. 



15 



17 



8-4 



0-9 



Marked necrosis. 



16 



17 



8-45 



Too small to 

 weigh. 





17 



17 



15 -4 



33 





18 



17 



13 -6 







Of course cells presenting complete degeneration are no longer capable of 

 giving rise to tumours. In fact they are rapidly taken up by phagocytes in 

 the days immediately succeeding transplantation, and it might be concluded 

 that growth was continued by cells which never even tended to degenerate. 

 Parts of the tumours which do not present this central necrosis are not of 

 uniform histological structure. Fig. 6 presents a histological appearance 

 common in these tumours (when preserved in strong Flemming solution) in 

 the portions apparently healthy to the naked eye. Dark and clear areas are 

 seen, the darkly stained portions which usually border on the connective 

 tissue being due to a progressive degenerative process in the cells. 



The cells which present this condition in any marked degree degenerate 

 immediately after transplantation, while growth is mainly continued by the 

 clear cells, and it is interesting to note that such degenerating cells form 

 a large proportion of tumours exhibiting early phases in spontaneous 

 absorption. 



The effects of eliminating degenerating cells at each transplantation for 

 the series 40 I to 48 E (vide p. 202) can be indicated by employing the 

 percentage of success to construct a diagram of the relative proportions of 

 implanted fragments which developed into tumours or were absorbed 

 respectively. The percentage of success in a batch of inoculations is a test 

 of the constitution of the parent tumour. If a series of large squares 



