PLATE i 
Characteristic appearance of vigorous and weak young com plants. 
A. —A healthy, vigorous plant, grown from disease-free seed. 
B. —A weak plant, stunted in size, and somewhat chlorotic, grown from diseased 
ed. 
C. —A weak plant, chlorotic and partly blighted, grown from diseased seed. 
D. ~A weak plant, very chlorotic and nearly dead, grown from diseased seed. 
All plants were of the same age and were drawn to the same scale. 
(630) 
