PLATE 8 
Spongospora subterranea in the roots of various hosts (fixed in Flemming ’s solution 
and stained with triple stain): 
Fig. A.—Section through a potato root affected with Spongospora subterranea . The 
portion to the left is healthy, while that to the right shows the increase in number 
and size of the host cells. Amebae in the cells are very numerous. X no. 
Fig. B.—Several cells from Solanum warscewiczii , showing the formation of “giant 
cells *' and their division into daughter cells. Note the tendency of the amebae to 
cluster around the host nucleus. X 2,600. 
Fig. C.—Section through a tomato root ( Lycoperstcon esculentum , showing effects of 
infection by Spongospora subterranea. Note the abnormal increase in number and 
size of the cells. The parasite is confined to the cortex, being entirely absent from 
the xylem. The amebae are numerous and generally clustered around the host 
nucleus. X 325. 
