PLATE 19. 



Bacterial black spot of the plum. 



Spots about six weeks old, except very few on the two right-hand plums of the upper row. Fruits about one-halt grown ; collected 

 July 24, 1902, from an orchard of Japaneie plunu in central Michigan. In this stage the plums (var. Hale) begin to crack open 

 and are attacked occasionally by fungi (MoniHa, etc.). Some tufts of Monilia may be seen on the outer, left-hand fruit, second 

 row from the bottom. Early stages of this disease are shown in figs. 70, 7 1 , and 72. 



