PLATE i 
A—Longitudinal section of stoma of Baart bearing a fully formed appressorium. 
B. —Three appressoria at one stoma of Baart. The guard cell is plasmolyzed. 
C. —Cross section of appressorium at a hair cell on the ridge of the leaf. 
D. —Appressorium formed on a dead cell at the apex of a rib on a leaf of Mindurn, 
a durum wheat. A secondary appressorium has formed from the first. 
E. —Cross section of a leaf of Baart, showing stoma and substomatal chamber and 
the fungus in the act of entering the stoma. 
F. —Longitudinal section of stoma of Mindurn, showing empty appressorium con¬ 
nected with the infecting hypha within. No substomatal vesicle formed. 
G. —Oblique longitudinal section from Mindurn, showing large substomatal vesicle 
and four infecting hyphae. 
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