KEY TO THE GENEKA 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 Smilax. 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 13. IRIDACEAE. 



27. Sisyrinchium. 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 mor.e 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. Jnglans. 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. Qiiercus. Fruit an acorn. The 1-celled, 1-seeded nut, supported 

 by a-i involucre (cup) of numerous scales. Trees or shrubs. 



