KEY, BASED UPON FLOWEKS. 3 



gr 2 . Flowers polygamous; stamens 5; tree armed with thorns usually 

 triple (Gleditschia) pods. 



Linear, many-seeded 28. GLEDITSCHIA TRIACANTHOS. 



Obliquely ovate, 1-seeded 109. GLEDITSCHIA MONOSPERMA. 



d?. Calyx superior adnate to the ovary; flowers in umbels; stamens 5; 

 styles 5; fruit drupe-like with 5 cells each with a single ovule (Aralia); 

 arborescent and armed with prickles 8. ARALIA SPINOSA. 



6 2 . Gamopetalom petals present and united ; stamens 



c. Fewer than the lobes of the corolla and inserted on it. 



112. OSMANTHUS AMERICANUS. 



c 3 . As many as the lobes of the corolla and alternate with them or fewer; ovary 

 superior; corolla irregular; ovary 2-celled (Bignoniacece) pod terete; leaves 

 simple (Catalpa) 89. C. BIGNONIODES. 



C 3 . 2-^tiines as many as the lobes of the corolla, inserted on its base and fila- 

 ments distinct (Ebenaceoe) 61. DIOSPYROS VIRGINIANA. 



6 3 . Apetalous without petals. 



C. Flowers not in catkins; pistil one, simple or compound, and the cells of the 



ovary containing 1-2 seeds each. 



d. Ovary inferior adnate its whole length to the calyx-tube 1-celled and 

 1-seeded; style 1, stigmatic down the side (Nyssa); fertile peduncles 



2-5-flowered 9. NYSSA MULTIFLORA. 



Single flowered and peduncle short and downy . 110. NYSSA OGECHE. 



Two or more flowers 9. N. MTJLTIPLORA. 



d*. Ovary superior free from the calyx. 



Stipules sheathing the stem ; trees with naked monoecious flowers ar- 

 ranged in heads. 13. PLAT ANUS OCCIDENTALS. 



-. Stipules not sheathing the stem or none. 

 /'. Ovules a pair in each cell of the ovary which becomes in 

 ff. Fruit a double samara (Acer). 

 fl. Leaves simple and palinately veined; flowers appearing 



i. With the leaves in pendulous corymbs 7. A. SACCHARINUM. 



i 3 . Before the leaves in short umbels, and 



Apetalous; young fruit wooly 26. A. DASYCARPUM. 



Petals present, linear-oblong; fruit smooth. .53. A. RUBRUM. 

 i 3 . After the leaves, in drooping racemes 



79. A. PENNSYLVANICUM. 



7* 2 . Leaves compound 54. A. NEGUNDO. 



gr 2 . Fruit a 1-celled and 1-seeded samara (Fraxinus). 

 h. Samara terete at base; leaflets petiolulate 



New growth smooth 10. F. AMERICANA. 



New growth pubsecent 31. F. PUBESCENS. 



h*. Samara broad at base 62. F. SAMBUCIFOLIA. 



/*. Ovules single in each of the 1 or 2 cells of the ovary. 



g. Anthers opening by uplifted valves; stigma single and entire 

 (Lauracece) flowers 



Perfect; calyx persistent ; leaves evergreen (Persea). 



113. P. CAROLINENSIS. 

 Dioscious, calyx deciduous, leaves deciduous ; involucre none 



(Sassafras) 32. S. OFFICINALE. 



gr 2 . Anthers extrorse ; stigma 2-cleft ; fruit a 



