KEY TO THE GENERA OF MANHATTAN PLANTS. 13 



numerous, flat, black, closely crowded crosswise in the 6 cavities. Leaves 

 long and sharp pointed). 



24. Vagnera. Berries nearly globular, in clusters terminating the stem. 

 Seeds 1-2. Perianth withering, persistent. 



25. Polygonatum Berries globular, from the axils of the leaves. Seeds 

 usually not more than six. 



Order 12. SMILACEAE. 



26 Smilux. Berry 3-celled, globular, seeds 6 or less. Herbs or woody 

 vines provided with a pair of tendrils near the base of the petiole. 



Order 18. IRIDACEAE. 



27. Msyrinchium. Capsules 3-celled, somewhat 3-angled, loculicidally 

 dehiscent. Flowers from a spathe. Grass-like herbs with equitant leaves 

 and a 2-edged stem. 



Order 14. ORCHIDACEAE. 



28. Gyrostachys Capsule l-celled,3-valved, with 3 parietal placentae 

 and innumerable minute seeds. Herbs. 



DICOTYLEDONE/E (Stem Exogenous). 



Order 15. JUGLANDACEAE. 



Fruit 1-seeded, but more or less 2-4-celled by partitions between 

 the lobes of the embryo. The pericarp consists of an inner bony inde- 

 hiscent portion and an outer more spongy or leathery covering. Trees. 



29. Juglans. Outer covering, spongy, indehiscent. 



30. Hicoria. Outer covering leathery or woody, splitting from the top 

 m>re or less completely into four valves. 



Order 16. SALICACEAE. 



Capsule, 1-celled, 2-4 valved; placentae parietal or basal. Seeds num- 

 erous, provided with a silky coma. Trees or shrubs. 



31. Populus. A cup-shaped disk at base of capsule. (Capsules ovate, 

 10-12 mm, 2-4 valved, in long, loose racemes. Placentae parietal). 



32. Salix. No cup-shaped disk. (Capsules tapering above into a 

 beak, 2-valved, in close racemes. Placenta basal). 



Order 17. BETULACEAE. 



33. Ostrya Akene smooth, enclosed in the inflated sac-like involucre , 

 the latter gathered in a short catkin. Tree. 



Order 18. FAGACEAE. 



34. Quercus. Fruit an acorn. The 1-celled, 1-seeded nut, supported 

 by ai involucre (cup) of numerous scales. Trees or shrubs. 



