PI/ATE 6 
A. —(i) Early stage of streak on seedling. (2) Mosaic dwarf on seedling. 
B. —(1) Streak plant in second year of disease, progeny of plant in same series as 
that in Plate 5, C. (2) Healthy plant of control lot. Green Mountain variety. 
C. —(1) Healthy hill* (2) Leaf-roll hill. These hills were in the same tuber unit. 
48108—23-6 
