’late 9 
A—On right, Green Mountain plant healthy except for current-season symptoms of rugose mosai 
indicated by the arrow. This is the twelfth hill from the east end of row 16 in section W-l (fig. 1), 
viewed from the south side. On left, healthy Green Mountain plant (thirteenth hill). Photographed ( 
July 30,1923. See Plate 8, C and D, for rugose mosaic from the seed tuber 
B and C.—On right, Green Mountain plant with leaf-rolling mosaic perpetuated by the seed piec 
On left, Green Mountain plant healthy except for current-season symptoms of leaf-rolling mosaic, inc 
cated by arrow. Photographed on July 30, 1923. For a healthy control see Plate 9, A, on left 
