Bui. 64, U. S. Dept. of Agrici 
ilture. 
Plate IV. 
{ 
4 X' 
m&F 
^Sj 
1 
8c * 
^3(p^j 
Lft^Jk, Z^t& J ^ 
£- ^H 
lfll^»*'^flr^sE 
jA ^BffH 1 . '?'-.'-'; * 
./ 
Fig. 1 .—Typical Potato Leaf-Roll in Seedling No. 16472, Alexander No. 1 
Red x Keeper. Houlton, Me., August, 1912. 
Fig. 2.— Potato Leaf-Roll. Advanced Stage in Seedling No. 304, Geheimrat 
ThielX Keeper. Houlton, Me., August. 1912. 
