KEY, BASED UPON FRUIT. 13 



e. Sunken at insertion of pedicel. 

 Globular 



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



Small, more or less 10-celled 59. AMELAS:CHIER CAXADENSIS. 



Flattened, globose, waxy, fragrant and very tart. 



83. PYRUS COROXARIA. 



e 2 . Not sunken at insertion of pedicel, pyriforui 57. PYRUS COMMUXIS. 



e? 2 . Not cartilaginous, 1-5 bony seeds. 



in. in diameter, red or yellow with white spots. 



58. CRATAEGUS PUNCTATA. 



\ in. in diameter, leaves round-ovate 86. CRATAEGUS C:OCCIXEA. 



4 in. in diameter, leaves wedge-obovate . . .85. CRATAEGUS CRUS-GALLI. 

 C 8 . Berry. 



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



61. DlOSPYROS VlRGOIAXA. 



Without persistent calyx, small, in thyrses 78. VITIS ^ESTIVALIS. 



c 9 . Fleshy with custard-like'edible pulp .- 76. ASIMIXA TRILOBA. 



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



84. PYRUS SAMBTJCIFOLIA. 

 6. s Dehiscent pericarp. 

 C. Subglobose, and 



(I. Coriaceous or woody, dehiscent by 



2-3 valves and containing one or very few large seeds with smooth shin- 

 ing coat and a large scar (^-Esculus), fruit prickly and leaflets 7. 



6. .ESCULUS HlPPOCASTAXTJM. 



e 2 . 4 more or less distinct valves (Gary a). 

 f. Epicarp thick and separating quite freely to the base; nut ridged and 



shell thick; nut globular ovoid. 

 g. Flattened. 



1 in. or less in length 36. CARYA ALBA. 



1 in. or more in length 64. CARYA SULCATA. 



g.- Not so much, flattened, usually 4 angled. 



90. CARYA TOMEXTOSA. 



/.* Epicarp thin and nuts small, shell thin and quite smooth. 

 Kernel very bitter, sutures of epicarp very prominent. 



37. CARYA AMARA. 

 Kernel slightly if at all bitter, sutures less prominent. 



91. CARYA MICROCARPA. 

 /. 3 Thicker and nut larger, more ridged and shell thicker. 



65. CARYA PORCINA. 

 (I.- Covered with spines ; dehiscent by 4 valves. 



Nuts sharply three-angled, 2 together, involucre, soft-prickly. 



16. FAGUS FERRUGINEA. 

 Xuts subovoid, flattened, 1-3 together, involucral spines very sharp and 



hard 40. CASTAXEA VESCA, var. AMERICANA. 



C. 2 Small, ovoid-lanceolate pods arranged in catkins, opening by two valves and 



containing numerous seeds furnished with silky down; leaves 

 (7. Orbicular-ovate ; petioles flattened. 



Dentate 18. POPULUS GRANDIDENTATA. 



Finely serrate, sharply pointed 72. P. TREMULOIDES. 



Sinuate-toothed, tomentose beneath 96. P. ALBA. 



Obscurely-serrate, with obtuse or rounded apex. 97. P. HETEROPHYLLA. 

 <1.' 2 Ovate, closely serrate, whitish and reticulate- veined beneath. 



47. P, BALSAMIFERA. 



f/. 3 Deltoid-ovate 48. P. MONTLIFERA. 



(I. 4 Broadly deltoid 73. P. DILATATA. 



fj. 5 Linear-lanceolate, tomentose on midrib above and petiole. 



45. SALIX NIURA. 

 d.* Lanceolate or elliptic. lanceolate, smooth above; capsules 



Sessile or nearly so 46. SALIX ALBA var. VITELLINA. 



With slender p'edicels 71. S. AMYGDALOIDES. 



C 3 . Linear compressed pods, opening by two valves. 



80. ROBINIA PSEUD ACACIA. 



