904 



III. EQUISETACE^. 



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

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

 containing antherozoids or archegonia, 

 into which the antherozoids enter for the 

 purpose of f&rtilization. 



I'quiietum. Elpe spore and elaters. 



B.ylaviatite. 

 Hhizome aud tubers. 



Bquisetum. 

 Spore Burroiinded by its elaters. 



Equisetum sylvaticum. 



Equisetum. Clypeole 

 furnished with 

 sporangia, ' 



