[Vol. 9, 1922] 



398 ANNALS OF THE MISSOURI BOTANICAL GARDEN 



Explanation of Plate 



PLATE 27 



Fig. 1. Section through a diseased spot of an oat leaf artificially infected, 

 showing portion of a substomatal cavity as well as neighboring cells and inter- 

 cellular spaces filled with bacteria. Magnified about 950 times. 



Fig. 2. Foxtail organism stained with carbol fuchsin, obtained from young 

 agar slant culture. Magnified about 1000 times. 



Fig. 3. Foxtail organism stained with Van Ermengem 's flagella stain. Mag- 

 nified about 1200 times. Bodies of the organisms, except the lower ones to the 

 left, retouched; all flagella remain untouched. 



Fig. 4. Cross-section of a diseased oat spot showing discoloration and collapse 

 of attacked cells. Magnified about 450 times. 



