S. DEPARTMENT OF AGRICULTURE 

 BUREAU OF PLANT INDUSTRY 



THE MOSAIC DISEASE OF SU( 



1.— A short piece of healthy leaf of the immune varietyKavan- 

 gire. 



2. — A piece of leaf of variety B-3922, showing isolated, more 

 or less rounded and irregular patches of normal color on a 

 background of pallid, affected tissue. 



3.— A piece of leaf of variety D-1 17, showing a mosaic pattern 

 somewhat similar to the above, but finer. 



