Dmeases of Plants. 
227 
The other disease manifests itself in raised spots of varying 
size on the surface of the tuber (see Fig. 2). At first the 
epidermis covers them, but by and by the skin bursts and 
exhibits an olive-green powder, giving to the potato a scurfy 
Fig. l.Styxanus Stemonitis Corda. A, Four fruiting bristles, b, The fruiting head 
C. Ripe spores. All magnified. 
appearance. The powder under the microscope is found to be the 
spore balls of the slime fungus Spongospora Solani Brunch. 
These balls form irregular roundish or elongated hollow bodies. 
