N. H. SWP]liLENGREBEL 
357 
At first some pansporoblasts are still to be seen among the sporo- 
blasts (Diagrams XII, XV), gradually they disappear and only sporo- 
blasts are left, which finally become spores. Consequently in Diagrams 
XIII and XIV the outlines of the spores are likewise to be seen. 
The sporoblasts contain two nuclei, similar in structure to those of 
the pansporoblasts. These nuclei are often situated in so close contact 
Diagram XVI. (Magnification of Diagram I.) A portion of the surface of a large cyst 
with sporoblast and spores (only the outlines of the spores are indicated). 
that they seem to constitute one large nucleus (Plate XVII, fig. 3). 
The protoplasm of the sporoblasts does not stain well; round the nuclei 
a clear space is left and in the protoplasm large vacuoles are to be seen 
(Diagram XVII). When the sporoblasts are just formed these vacuoles 
are not yet present. 
These intermediate stages, leading to the formation of the sporo¬ 
blasts, are to be observed only in the smaller cysts, the lai’ge ones only 
contain sporoblasts and spores (Diagram XVI). 
