PLATE i 
A. —Alternaria mali. Cultures of forms A and*B in a Petri dish of corn-meal agar. 
Each has broken up into the two forms. 
B. —Spots on an apple leaf showing about the original central spot the type of 
enlargements caused by Alternaria mali . 
C. —Conidia of Alternaria mali from a culture on corn-meal agar. X440. 
