77 



The Prothalliiim produces tlie Sexual , 



Organs / Oophyie 



The Sexual Organs produce the Embryo i Generation. 

 The Embryo produces the Fern Plant / 



Note that the alternation of generations in Sela- 

 ginella and Aspidium is similar to each other, but 

 directly opposite to that exhibited in Marchantia and 

 Fnnaria. 





