904 



III. EQUISETACE^E. 



globose smooth spores, accompanied by 2 spathulate filaments (elaters) ; spores in germi- 

 nation forming a prothallus, like that of Ferns, on which are developed antheridia 

 containing antherozoids or archegonia, 

 into which the antherozoids enter for the 

 purpose of fertilization. 



Ki/nisetum. 

 Spore surrounded by its etaters. 



Equisetum tyltaticum. 



Equifetum. Clypeole 



furninhe<i witli 



aporangia. 



Equisetum. 

 Dehiscing 

 sporangium. 



