MONOCOTYLEDONES 189 



19. PontederiaeejE. 



20. Philydraoese. 



21. Xyridacese. 



22. Mayacese. 



23. Commelynaceffi. 



Series 4. — Ca lycinm. 

 Cliaracters. — Perianth herbaceous; inner whorl small; 

 very rarely sub-petaloid. Ovary free. Albumen copious. 

 Order 24. JuncaceEE. 

 25. Palmacese. 



Series 5. — Nudiflorm. 

 Character s. — Perianth absent or reduced to scales or setas. 

 Ovary superior vfith a solitary carpel, or if of many carpels then 

 syncarpous. Ovules 1-go. Seeds most frequently albuminous. 

 Order 26. Pandanaces. 



27. Typhaeeae. 



28. Aroidacese or Araceae. 



29. Lemnacese. 



Series 6. — ApocarptB. 

 Characters. — Perianth uniseriate or absent. Ovary supe- 

 rior. Carpels distinct or sohtary. Seeds exalbuminous. 

 Order 30. Triuridaceae. 



31. Alismaceae. 



32. Butomace^. 



33. Naiadacese. 



34. JuncaginaceEe. 



Series 7. — Oltmiacece. 

 Characters. — Flowers in capitula or spikelets, disposed 

 under bracts or glumes ; very often imbricated, sessile ; segments 

 of perianth small, scale-like, glumaceous or absent. Ovary either 

 with one ovule, or divided into monovulate loculi. Seeds al- 

 buminous. 



Order 35. Briocaulacese. 



36. Desvauxiacese. 



37. Kestiaceae. 



38. Cyperaceae. 



39. Graminaceae. 



