PLATE 3 
Pythiacystis gummosis on lemon tree from inoculation on November 23, 1912, with 
pure culture of Pythiacystis dtrophthora, 
A. —Extent of mvaded portion (inside of chalk line) and gum formation on June 
■6, 1913. The ftmgus was isolated from several places near chalk line at this date. 
B. -^ame tree iPter bark was cut, showing invaded zone (black) and a part of the 
outer gummous zone (shaded), which extended upward and downward under live 
‘ bark. 
C. —Same tree in September, 1914, showing new bark pushing in over wound. 
D. —Same tree in June, 1920, showing increase in the new bark covering the edges 
of the original wound. 
