PLATE 51 



Urophlyctis alfalfae: 



Section of diseased bud scale attacked by U. alfalfae, showing a group of eight well- 

 developed cavities a-h and their relation to the host tissue. Many of the cells adjacent 

 to the cavities have divided at unusual angles, giving the tissue a characteristic appear- 

 ance. In b the host cytoplasm and fungous material stain unusually deeply, as the 

 result perhaps of general infiltration with some diffusing substance. Drawn with 

 the aid of the camera lucida. Approximately X 417. 



