PLATE XIII. 



Fig. 1. Section through a group of free spore-balls of Spongospora. 



Fig. 2. Three spore-balls in section, from type herbarium material. 



Fig. 3. A healthy potato-cell, showing nucleus surrounded by small starch -grains. 



Fig. 4. Copy of Massee's figure of potato-cell to show Spongospora myxamabcB, 

 surrounding host-nucleus. 



Fig. 5. Several intra-cellular spore-balls : 



n host-nucleus in impoverished condition ; 

 s, s, s, starch grains. 



Fig. 6. A single host-cell occupied by vacuolated Plasmodium (p) (x 2000). 



Fig. 7. A potato-cell of the type herbarium material, occupied by Spongospora 

 Plasmodium. 



Fig. 8. A host-cell, one half occupied by a spore-ball, the other half by the 

 protoplasmic and starch contents. Two feebly-staining host-nuclei 

 are present in this cell [n). 



