228 Annual Report for 1907 of the Consulting Botanist. 
having somewhat the appearance of a minute sponge, hence the 
name given to the fungus. The disease was first observed 
by Brunchhorst, in Holland, in 1886, and has been detected 
thereafter in several European countries. It has been noticed 
and has been described by Professor Johnson, of Dublin, in 
1906. Though the disease and its cause are known, there has 
yet to be discovered the manner in which the fungus obtains 
entrance into the tuber and develops there. Experiments 
instituted for this purpose are being prosecuted. 
Fig. 2.— Tubers of potato attacked by Spongoxpora Solnni Brunch. 
Fig. X—Spougospora Solnni Brunch. A, Spore balls magnified. B, A spore baU more 
liighly magnified. C, Mass of single spores, D, Separate spores, treated with staining 
re-agents. 
