250 



This iiu'lhod ol' cuUiNiilion ol' in;ili<^n;int cells is very simple 

 and easy lo ixTt'onii. Nol niuch Irainiiiff in culhirc Icchni- 

 (|uc' is necessary lo carry on Ihcsc cells iddelinilely. 11 is 

 ralhei' aslonishin^ lo see how easy these ciilliires are niulli- 

 plied lo a great cxleiil. in a week oi" so. il is |)ossil)le lo 

 make so many cultures. Ihal one person would nol have 



Fig. 58. 

 Represents a section through a culture of the Rous sarcoma after a couple of 

 month's cultivation. An infiltration of the muscle fragment can be seen. 



time lo transfer the cultures or keep Ihcm going. Il is scar- 

 cely possible to loose Ihe strain, il' nothing extraordinary 

 happens, such as infection. 



1 have observed, thai o n e si n g 1 e s a r coma cell 

 is able to contaminate a piece of muscle and in as snort a 



