PLATE 2 
A. —Sectional view of large wart developed from terminal bud of tuber. 
B. —Sectional view of aerial wart. Note general appearance of wart and central 
location of vascular tissue. 
C. —Sectional view of large wart on tuber. The vascular tissue shows the arrange¬ 
ment which is typical of petiolar or midrib bundles. 
D. —Sectional view of large wart on tuber. The apparent solid structure is an aggre¬ 
gate of compressed, modified leaves. 
E. —Sectional view of large wart on stolon. The branching is often so intricate that 
only the aid of the microscope will reveal the component parts. 
