liO.) 



The technique is more simple than any of the others 

 for keeping strains of tissue cells in vitro, and practically 

 no training is necessary. 



The investigation of numerous })rol)lems of importance 

 is rendered possible by means of this method. We have 

 here an inexpensive and simple way of carrying on the 

 virulent sarcomatous tissue cells from piece to piece of 

 fresh muscular tissue. 



Fig. 62. 

 Represents a section of a tumor from a chicken whicti has been inoculated 

 with a culture of sarcoma cells, that has undergone 40 passages in vitro. 



By studying the Ron s's chicken sarcoma in vitro accord- 

 ing to the method already described, several new facts 

 have been discovered already, as to the biological character 

 of these cells. From the cultivation of the malignant sarcoma 

 cells it is learned that these cells are able to synthesisi© 

 their own living protoplasm from the serum constituents 



