PLANT BACTERIA, VOL. 3. 



PLATE 32. 



Four Petri-dish poured-plates of Bacterium solanacearum (Virginia strain), showing the effect of freezing. 



.1 and B, plates poured before freezing; C and D, corresponding plates inoculated with the same carefully measured amount of the 

 bouillon culture, but after freezing, i e., as soon as the culture was thawed. The plates were incubated for some days at 30 C. 

 The large dark colonies are on the surface, the large pale colonies are between the bottom of the dish and the agar, the dot-like growths 

 are colonies buried in the body of the agar. Photographed Feb. 20, 1904. 



