561 



Wood of stem arranged in a confused 

 manner, youngest in the centre, 

 cotyledon single. 



Leaves parallel-veined, permanent; 

 root much like the stem inter- 

 nally 4. Endogens. 



Leaves net-veined, deciduous ; root 

 with the wood in a solid, con- 

 centric circle 5. Dictyogens. 



Wood of stem arranged in a concentric, 

 or uniform manner, youngest at 

 the circumference ; cotyledons 

 two or more. 



Seeds quite naked 6. Gymnogens. 



Seeds enclosed in seed-vessels 7. Exogens. 



Class L Thallogens. 



Alliance L Algales. — The Algal Alliance. 



1. Diatomacese, Brittleworts. 



2. Confervaceae, Confervas. 

 .3, FucacesD, Seawracks. 



4. Ceramiacese, Rosetangles. 



5. Characeae, Charas. 



Alliance 2. Fungales. — The Fungal Alliance, 



6. Agaricaceae. (Hymenomycetes). Toadstools. 



7. Lycoperdaceae. (Gasteromycetes). PufT-balls. 



8. Uredinacese. (Coniomycetes). Blights. 



9. Botrytaceae. (Hyphomycetes). Mildews. 

 10. Helvellaceae. (Ascomycetes). Morels. 

 IL Mucoraceae. (Physomycetes). Moulds. 



Alliance 3. Lichenales. — The Lichenal Alliance. 



12. Graphidacese, Letter-Lichens. 



13. Collemaceae, Jelly -Lichens. 



14. Parmeliaceae, Leaf- Lichens. 



Class 2. Acrogens. 



Alliance 4. Muscales. — The Muscal Alliance. 



15. Ricciaceae, Crystalworts. 



16. Marchantiaceae, Liverworts. 



17. Jungermanniaceae, Scalemosses. 



