250 



BACTERIAL DISEASES OF PLANTS 



FIG. 189. -A. Fermentation-tube milk culture of Bacillus aroideae. The 

 closed arm is full of gas (all CO 2 ) and so is the U. From .r upward, whey; and 

 downward, curd. Curd also in base of the closed arm. Inoculated January 15, 

 1915. Photographed February 10, 1915. 



B. Same as A but 48 hours later when all the gas has been absorbed by ad- 

 dition of a strong solution of sodium hydroxide. 



