12 HOUGH'S AMERICAN WOODS. 



fir 4 . Flattened-globose ; leaves 



Sinuate-pinnatifid with wide sinuses 94. QUERCUS PALUSTRIS 



Obovate-spatulate, entire 118. QUERCUS AQUATICA. 



f*. Top-shaped, ^ enveloping the acorn ; scales thin and coarse ; 



Inner bark of tree reddish 69. Q. COCCINEA . 



Inner bark yellowish 93. Q. TINCTORIA. 



/ 4 . Turbinate, enveloping the nut 192. Q. WISLIZENI. 



d*. Inclosed in an indehiscent involucre and with edible kernel (Juglans). 

 e. Subglobose and 

 /'. Glabrate or pubescent; nut 



Deeply sulcate 233. J. RUPESTRIS. 



Obscurely sulcate . . 190. J. CALIFORNICA. 



/". Roughly dotted, l-2 in. in length and nut deeply sulcate. .35. J. NIGRA. 



e' 2 . Subovoid, 2-2| in. long; nut deeply sulcate 14. J. CINEREA. 



d 3 . Club-shaped, short, surrounded with stiff hairs, tipped with the persistent, 

 recurved style and arranged in globular heads, which are 



Solitary or in pairs 13. PLATANUS OCCIDENTALS. 



2-4 together in a moniliform raceme, achenia truncate at apex 



232. PLATANUS WRIGHTII. 



2-7 together achenia pointed at apex 135. PLATANUS RACEMOSA. 



d 4 . Achenium-like, small and borne in short catkins, 



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



41. OSTRYA VIRGINICA. 



Subtended by a large leafy bract 42. CARPINUS CAROLINIAN A. 



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



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



attached 3. TILIA AMERICANA. 



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



114. PLANERA AQUATICA. 

 c 8 . Pod (legume) which is 



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

 d' 2 . 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 5 . 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. 



/ 3 . Oblong, i-f in. long 209. PYRUS RIVULARIS. 



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



eJ 2 . Not cartilaginous, 1-5 bony seeds : color 



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



Dull red, thickness 



f in. (sometimes yellow 7 ) with white dots 58. CRATAEGUS PUNCTATA. 



i 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 VIRGINIANA. 



d*. Without persistent calyx-lobes and smaller 



e. In thyrses 78. VITIS JESTIVALIS. 



e 2 . In compact-racemes and 



Hoary-tomentose 131. GARRYA ELLIPTICA. 



Smooth and flattened- globose 133. ARCTOSTAPHYLOS PUNGENS. 



