12 KEY, BASED UPON FRUIT. 



A Turbinate, enveloping the nut 192. Q. WISLIZENI. 



d 2 . Club-shaped, short, surrounded with stiff hairs, tipped with the persistent 

 recurved style and arranged in globular heads, which are 



Solitary 13. PLAT ANUS OCCIDENTALS. 



2-7 together in a moniliform spike 135. PLATANUS RACEMOSA. 



d 8 . Acheniu in-like, small and borne in short catkins, 



Inclosed in a membranous inflated sac, catkin hop-like. 



41. OSTKYA VIRGINICA. 



Subtended by a large leafy bract 42. CARPINUS CAROLINIANA. 



c 5 . Nut-like, dry, not invested with an involucre, 



Snioothish, globose, about i in diameter, in cymes with leaf-like bract 



attached . 3. TILIA AMERICANA. 



Rough, with scale-like points, ovate, coriaceous. 



1.14. PLANERA AQUATIC A. 

 c 6 . Pod (legume) which is 



d. Oblong, flat, about 2 in. broad and curved . .27. GYMNOCLADUS CANADENSIS. 

 d*. Linear or nearly so 



10-18 in. long, contorted and twisted 28. GLEDITSCHIA TRIACANTHOS. 



4-6 in. long, subterete, compressed between the seeds and thick- 



valved 129. PROSOPSIS JULIFLORA. 



3-4 in. long, 2-8-seeded and thin valved.. 128. CERCIDIUM TORREYANUM. 

 d 3 . Obliquely ovate (1-2 in. long), long stalked and mostly 1-seeded. 



109. GLEDITSCHIA MONOSPERMA. 



d 4 . Ovate, compressed and with accrescent calyx 154. DALEA SPINOSA. 



d & . Closely twisted spiral 205. PROSOPIS ODORATA. 



c 7 . Pome ; endocarp and testa 

 d. Cartilaginous ; fruit 

 e. Sunken at insertion of pedicel, 

 f. Globular 



Large, 1 in. or more, distinctly 5-celled 30. PYRUS MALUS. 



Small, more or less 10-celled .59. AMELANCHIER CANADENSIS. 



/*. Fattened-globose, waxy, fragrant and very tart.. 83. PYRUS CORONARIA. 



/*. Oblong, |-f in. long. 209. PYRUS RIVULARIS. 



c 2 . Not sunken at insertion of pedicel, pyriform 57. PYRUS COMMUNIS. 



d* Not cartilaginous, 1-5 bony seeds : color 



Black, subglobose, i in. in diameter 210. CRATAEGUS DOUGLASII. 



Dull red, thickness 



f in. (sometimes yellow) with white dots 58. CRATAEGUS PUNCTATA. 



in. ; leaves thick, glossy above 85. CRATAEGUS CRUS GALLI. 



Bright scarlet and somewhat oblong, | in. long . . 86. ( 'RATAEGUS COCCINEA. 

 C 8 . Berry. 

 d. With persistent thickish calyx-lobes, large (about 1 in. or more), 



61. DlOSPYROS VIRGINIAN A. 



e2 2 . Without persistent calyx-lobes and smaller 



e. In thyrses 78. VITIS ^ESTIYALIS. 



e 2 . In compact-racemes and 



Hoary -tomentose 131. GARRYA ELLIPTICA. 



Smooth and flattened-globose 133. ARCTOSTAPHYLOS PUNGENS. 



e 3 . In open panicles 132. ARBUTUS MENZIESII. 



e 4 . Singly on the jointed flattened stem H34. OPUNTIA TUNA. 



c 9 . Fleshy, with custard-like edible pulp 76. ASIMINA TRILOBA. 



c 10 . Berry-like pome, f in. in diameter and borne in dense clusters. 



84. PYRUS SAMBUCIFOLIA. 

 c 11 . Hesperidum seeds in juicy pulp and rind leathery. 



Subglobose. flattened at the ends 103. CITRUS AURANTIWM. 



Globose-oblong, mammillate at the extremity 104. CITRUS LIMONUM. 



c 12 . Achenium. 



3-4-angled and with membranous wing-like margins. 



108. CLIFTONIA LIGUSTRINA. 

 Linear oblong, tipped with the prolonged tail-like style. 



130. CERCOCARPUS PARVIFOLIUS. 



c 13 . Baccate but with dry spongy pericarp 175. YUCCA ARBORESCENS. 



6 2 . Dehiscent pericarp, 

 c. Subglobose, and 



