250 HEREDITY AND EVOLUTION IN PLANTS 



3-5, Vascular Cryptogams 



Stem smooth, leaves spirally arranged, sporangia single . Clubmosses 3 

 Stem with ridges and joints, leaves whorled, sporangia 



several Horsetails 4 



Woody cylinder discontinuous (i.e., with foliar gaps), 

 leaves large, sporangia below PTEROPSIDA 



Without seeds Ferns 5 



With seeds SPERMATOPHYTA (PHANEROGAMS) Seed Plants 6 



Ovules naked, endosperm formed before fertilization . Gymnos perms 6 



Sperms ciliated Early Gymnosperms 6a 



Sperms not ciliated Late Gymnosperms 66 



Ovules enclosed, endosperm formed after fertilization . Anglos perms 6c 



3. Clubmosses (Lcpidophyla (Bessey)) 

 Lycopodiales Selaginellales 

 Isoetales (?) Lepidodendrales (Fossil) 

 Psilotales 



4. Horsetails (C 'alamo phyla (Bessey), Sphcnopsida (Scott), Arthro phyla 



(Berry)) 



Spenophyllales (Fossil) Calamariales (Fossil) 



Pseudoborniales (Fossil) Equisetales 



5. Ferns (Pterido phyla, in restricted sense; FilicinecB). 

 Eusporangiata Leptosporangiata 



Primofilices (Ccenopteridese) Osmundales 



Marattiales Polypodiales 



Ophioglossales Marsiliales 

 (Isoetales?) 



6. Seed-Plants 



(6a &* 66 Gymnos perma of Brongniart) 



6a. Early Gymnosperms (Cycado phyla (Nathorst) except Ginkgoales; 



Archigymnospermce (Jeffrey)) 



Cycadofilicales (Fossit) Cordaitales (Fossil) 



Hemicycadales (Wieland) = Ginkgoales 



Bennettitales of Potoni6 (Fossil) 

 Cycadales 



66. Late Gymnosperms (Conifene (Hallier); Metagymnospermae (Jef- 

 frey); SlroUlo phyla (Bessey)) 

 Tuxales Finales 



Araucariales Gnetales 



