CONTENTS. 
Preface .ix 
Introduction . xi 
Key to the Orders.xvii 
Subkingdom Pteridophyta. i 
Order i. Ophioglossales. i 
Family i. Ophioglossaceae . i 
Order 2. Filicales . 1 
Family 2. Polypodiaceae . 1 
Order 3. Salviniales . 5 
Family 3. Marsileaceae. 5 
Order 4. Equisetales . 5 
Family 4. Equisetaceae . 5 
Order 5. Isoetales . 5 
Family 5. Isoetaceae . 5 
Order 6. Lycopodiales . 6 
Family 6. Lycopodiaceae . 6 
7. Selaginellaceae . 6 
Subkingdom Spermatophyta . 7 
Class 1. Gymnospermae . 7 
Order 7. Pinales . 7 
Family 8. Pinaceae . 7 
9. Juniperaceae . 9 
Order 8. Gnetales . 10 
Family 10. Ephedraceae . 10 
Class 2. Angiospermae . 11 
Subclass 1. Monocotyledones . 11 
Order 9. Pandanales . 11 
Family 11. Typhaceae . 11 
12. Sparganiaceae . 11 
Order 10. Naiadales . 12 
Family 13. Zanichelliaceae . 12 
14. Naiadaceae . 13 
Order 11. Alismales . 13 
Family 15. Scheuchseriaceae . 14 
16. Alismaceae . 14 
Order 12. Hydrocharitales . 15 
Family 17. Elodiaceae . 15 
Order 13. Poales . 15 
Family 18. Poaceae . 15 
19. Cyperaceae . 57 
Order 14. Arales . 74 
Family 20. Araceae . 74 
21. Lemnaceae . 74 
Order 15. Xyridales . 75 
Family 22. Commelinaceae . 75 
23. Pontederiaceae . 75 
Order 16. Liliales . 76 
Family 24. Melanthaceae . 76 
25. Juncaceae . 77 
26. Alliaceae . 81 
v 
