Division I. EMBRYOPHYTA ASIPHONO- 

 GAMA (ARCHEGONIATAE). 



Plants with marked alternation of generations. Sexual 

 geiieratioji {gametophyte) bearing antkeridia, in which 

 spermatozoids arise, and archegonia, each containing an 

 egg-cell. The fertilized egg-cell gives rise to an embryo, 

 which for some time or throughout life remains attached 

 to, and nutritively dependent on, the gametophyte. The 

 embryo grows into the asexual generation {sporophyte), 

 eventually producing spores, which again give rise to the 

 gametophytes. 



[Subdivision i. Bryophyta (not included in this 

 work). Gametophyte thalloid or leafy, free living. 

 Sporophyte (sporogonium) leafless, attached through- 

 out life to the gametophyte : no true roots.] 



Subdivision 2. PTERIDOPHYTA. Gametophyte 

 {protkallus) thalloid, usually vegetating independently, 

 rarely completely enclosed in the spore. Sporophyte a 

 cormophytic plant with true leaves and roots, early 

 becoming independent of the gametophyte, and bearing 

 spores in separate organs {sporangia) borne on or in 

 connection with the leaves. 



Class I. EQUISETARIAE. Leaves generally 

 small in relation to the stem, in alternating whorls. Stele 

 with separate collateral bundles. Peltate sporangiophores 

 aggregated in cones. Sporangia bulky, attached to the 



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Librarv 



