PLATE 70 
A. —Normal rust infection on a leaf of Dutch Case Knife developed in the green¬ 
house. Number of uredinia 544, leaf area 7.93 square inches, sori per square inch 
68.6. Photographed 16 days after inoculation. Approximately natural size. 
B. Abortive rust infection on a leaf of Improved Goddard. Number of flecks 
140, leaf area 10.78 square inches, flecks per square inch 12.9. Photographed 16 
days after inoculation. Approximately natural size. 
