188;).] 



PUBLIC DOCUMENT — No. 33. 



137 



Fig. 1. Two potatoes, "Beauty of Hebron,"' from Station plats, badly 

 affected by " scab," illustrating the usual form of the disease. 

 From ijhoUxjraphs. Five-sixths natural size. 



Fig. 



Section taken at right angles to the surface of a healthy potato 



tuber, showing its normal structure. 

 sk. The " skin " of the tuber, of tabular coi'k-cells. 

 I. A lenticel, filled with rounded cork-cells. 

 p. The parenchymatous tissue, which forms the bulk of the 



tubers, containing starch-grains, st. 

 Original. Magnified one hundred diameters. 



