PLATE 2 
Closed and half-closed sori. 
A. —Aggregation of sori at the stem end of a tuber from Scotland. 
B. —Stripe arrangement on tuber taken from a consignment of Danish potatoes. 
C. —Semicircle of pustules. 
D. —Promiscuous distribution of pustules over the surface of the tuber. 
C and D were received from England. 
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