PLANT BACTERIA, VOL. 3. 



PLATE 40. 



Longitudinal section of three tobacco stems inoculated when much younger with Bacterium 

 solanacearum from a Florida potato. 



Wilt of the foliage did not occur. The inoculations were made by needle-pricks Sept. 19, 1905, and the photograph 

 Feb. 20, 1906. Surface green and sound, many green leaves; pith diseased (mottled brown and white). Bac- 

 teria very numerous in the stained parts of 496 and present to a less extent in the others. Botrytis had also 

 entered 496. This photograph represents best results obtainable with the strain of Bad- solanacearum used, which 

 was one that had lost much of its virulence. 



