152 THE EVOLUTION OF CONTINUITY 



Aqueotts Environment. 



Teheestbiaii Envtbonment, 



Side-lines of Existing 



and Extinct 



Speciea. 



Discontinuously 

 Multicellular 



Filamentous 



Discontinuously 

 Zooidal ' 



Continuously 

 Zooidal 



Discontinuously 

 Megazooidal 



Continuously 

 Megazooidal 



Main line of Evolution 

 of Continuity through 

 Evanescent Primi- 

 tive Types. 



Discontinuously 

 Multicellular 



Filamentous 



Discontinuously 

 ' Zooidal 



V 



Continuously^ 

 Zooidal 



Discontinuously 



,, Megazooidal 



Continuously 

 Megazooidal 



Only Side-lines, derived from 



Aqueous Types. No Main 



Line of Evolution oi 



Continuity. 



Discontinuously 

 Multicellular 



Coenocytio 



Filamentous 



, Segmental 



» Continuously Zooidal of 

 highly evolved type 



Simpler Segmental 

 Higher Segmental 



Fro. 46. 



