Placosphaera /^ 

 stageO VS'^ 



Urococcus 

 phase 



Pseudociliate 

 stage 



Juvenile 'Aprocvstrs' I 

 colony form p 



Aplanospore 



Fig. 13 Top: Life history of Schizochlamys. (After Thompson.) 

 Bottom: Life history of Tetraspora gelatinosa. (After Hirose.) 



established but may well take place at swarmer formation in the 

 attached colonies. 



In the allied genus Schizodictyon the gelatinous mass is fenes- 

 trated giving a net-like appearance. The net type of structure is a 

 morphological development that has occurred separately in a 

 nimiber of different algal groups. 



Apart from Tetraspora gelatinosa^ another genus in which a life 

 cycle has been fully worked out is Schizochlamys (Thompson, 



36 



