KEY, BASED UPON FLOWERS. 



k : .# 2 *.:<?a.l#x*-npei I ior 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.' 



^ 2 . Gamopetalous petals present and united; stamens 2-4-times as many the 

 lobes of the corolla, inserted on its base and filaments distinct (Ebenacecc}. 



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. 



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

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

 ing each two or more flowers 9. JS. MULTIFLOKA. 



d? Ovary superior free from the calyx. 



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

 ranged in heads 13. PLATANUS OCCIDENTALS. 



C 2 . Stipules not sheathing the stem or none. 

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

 g* Fruit a double samara (Acer). 



h. Leaves simple and palmately veined; flowers appearing 



*. With the leaves in pendulous corymbs 7. A. SACCHARIN LM. 



t' 2 . Before the leaves in short umbels, and 



Apetalous; young fruit wooly 26. A. DASYCARPUM. 



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



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



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

 h. Samara terete at base; leaflets petiolate 



New growth smooth 10. F. AMERICANA. 



New growth pubescent 31. F. PUBESCENS. 



7* 2 Samara broad at base 62. F. SAMBUCIFOLIA. 



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



ff. Anthers opening by uplifted valves; stigma single and entire: flowers 



dioecious; stamens 9; anthers 4-celled; involucre none; fruit an 



ovoid, blue drupe with reddish pedicel. .32. SASSAFRAS OFFICINALE. 



j/ 2 . Anthers extrorse; stigma 2-cleft; fruit a 1-celled samara winged all 



round ( Ulmus). 

 h. Flowers nearly sessile; samara not fringed; ciliate; leaves very 



rough above 11. IT. FTLVA. 



Tfc 2 . Flowers on drooping pedicels; samara ciliate-f ringed ; leaves 



smooth. 



Bud-scales glabrous; flowers fascicled; branches not corky- 

 winged 33. U. AMERICANA. 



Bud scales downy -ciliate; flowers racemed; branches corky- 

 winged 34. U. RACEMOSA. 



gr 3 . Anthers introrse; fruit a dark-purple drupe; leaves long-taper- 

 pointed 12. CELTIS OCCIDENTALS. 



C 2 . Flowers diclinous and one or both sorts in catkins. 

 d. Only one sort (the staminate flowers) in catkins. 



e. Fertile flowers single or clustered; fruit naked; leaves pinnately com- 

 pound (Juglandacew}. 



f. Corolla present in the fertile flowers; fruit with valveless epicarp 

 (Juglans). 



gr. Fruit ovate, oblong and viscid-hairy 14. J. CINEREA. 



</ 2 . Fruit globose, roughly dotted (not viscid-hairy) 35. J. NIGRA. 



/" 2 . Corolla not present in the fertile flower; fruit with usually 4-valved 



epicarp (Carya) which is 

 gr. Thick; valves separating to base; bark in loose plates; 



Leaflets 5; nut small . 36. C. ALBA. 



Leaflets 7-9; nut large 64. C. SULCATA. 



gr 2 . Thin; valves not freely separating to base; bark close; nut quite 



smooth and 

 Thick- shelled; kernel moderately bitter; leaflets 5-9. 



65. CARYA PORCINA. 

 Very thin-shelled- kernel very bitter; leaflets 7-9. 



37. CARYA AMARA. 



