PLATE I 
St^es in the^development of arsenical spray injury on apple foliage. 
A. —fiiree days after spraying. 
B. —Four days after spraying. 
C. —Five days after spraying. 
D. —Seven days after spraying. 
E. —^Ten days after spraying. 
F. —Twenty-five days after spraying. 
(538) 
