12 KEY TO THE GENERA OF MANHATTAN PLANTS 



8. Cyperus. Scales 2-ranked, strongly keeled. Akene flat or tri- 

 angular, naked, spikelets in spikes or heads. 



9. Eiophorum. Scales in this and the following genera, several 

 ranked. Akene triangular, surrounded by several long bristles. 



10. Seirpus Bristles around akene few and short or none. 



11. Eleocharis. Spike single terminating the naked stem. Akene 

 surrounded by bristles and tipped with a tubercle. 



12. Carex. Akene enclosed in a sac. 



13. Fuirena. Scales with an awn on the back below the tip. 



Order 7. ARACEAE. 



14. Arasaema Berries crowded on a fleshy axis, usually surrounded 

 or supported by a more or less rolled up leaf (spathe). (Berries scarlet, 

 1-celled, 1 to few seeded. Herbs). 



Order 8. COMMEL1NACEAE. 



Capsule 2-3-celled, seeds 3 or more, dehiscence loculicidal. Herbs. 



15. Commelina Capsule 3-celled (3-seeded, 1 cell indehiscent. Fruit 

 enclosed in spathe. ) 



16. Tradescantia. Capsule 3-celled, all dehiscent. (Seeds about 3, 

 elliptical, flattish, on one side a pit with radiating ridges, on the other 

 a longitudinal ridge with transverse wrinkles on each side.) 



Order 9. PONTEDERIACEAE. 



17. Heter anther u. Capsule more or less completely 3-celled by the 

 intrusion of the placentae, seeds numerous. Aquatic herbs. (Capsule 

 enclosed in the spathe.) 



Order 10. JUNCACEAE. 



18. Juncus Capsule 3-celled or 1-celled with 3 parietal placentae, lo- 

 culicidally 3-valved. Divisions of perianth 6, scale-like, persistent. 

 Seeds small and numerous. Grass-like herbs. 



Order 11. LI LI ACE AE. 



Fruit 3-celled, a berry or capsule. Perianth inferior. Herbs. 



19. Zygadenus. Capsule 3-lobed. (Septicidally 3 valved at summit. 

 Seeds about 6, angled, oblong. 



20. Allium. Capsules in umbels on naked stems, supported by a 1 to 

 3-valved spathe, loculicidally dehiscent. Seeds 3-6, usually angular. 

 Plant with the odor of onions. 



21. Notkoscordum. As in Allium but no oder of onions. 



22. Erythronium. Capsule loculicidal, solitary, nodding. Low plants 

 with 2 leaves and a scape. 



23. Yucca. Capsules several (large and woody, imperfectly 6-celled, 

 by a false partition from the back of each cell, 6-valved at summit. Seeds 



