PHAGOCYTOSIS 



25 1 



and planting it on a suitable culture medium, on which the cell 

 died ; but the spore survived, showing that it was taken up with- 

 out any previous injury. He also traced in a very clear and full 

 manner the steps by which a tubercle bacillus of absolutely normal 

 appearance, and apparently vigorous and healthy, undergoes 



F 1G . 53. PROCESS OF ABSORPTION OF TUBERCLE BACILLI IN GIANT CELLS. 

 a, Unaltered bacilli ; b, c, d, and , various stages in the process. 



degeneration, death, and absorption in the giant cell. His case 

 was proved to the hilt in the case of certain bacteria, whereas his 

 opponents proved theirs in others. They were dealing with 

 immunity of different types, and the time was not ripe for the 

 solution of the problem. 



The views of another school which sprang up at this point, and 

 which attempted to reconcile these two views, are of more impor- 



