TliE PLANT W()RT>I). VoL. III. 



Plate I. 



Nostoc filament, h heterocyst. x 450. 



Tolypothri.x filament with false branch, x a25. 



Tolypolhrix filament in process of forming branches. 



Scytonema filament showing twin branches. 



Gloiotrichia filament, x 225. 

 . .„. ^. .Spirogyra. Vegetative cell, x 42. ~ 

 Fig. 7. Same after staining. 

 Fig. 8. Conjugating filaments. 

 Fig. 9. Mlcrasterlas, z 200, 



Fig. 1. 

 Fig. 2. 

 Fig. 3. 

 Fig. 4 

 Fig. 5. 

 Fig. tS. 



