522 



BACTERIAL DISEASES OF PLANTS 



Yic 392— Block of raw potato showing experimental production of small 

 tumors'like the accidental ones of Fio. 390. The pared sterile potato flesh restmg 

 in wet cotton, was sealed into a test tube February 7, 1919, kept m the dark 

 at room temperature, 22° to 25°C., and photographed April 17. X 5. bmall 

 shoots were torn away at X, which was the l)ottom of the block bedded m the 

 wet cotton. 



