LEAF INDEX. 35 



SIMPLE- ALTERNATE-SERKATE or Toothed or Crenate. Continued. (IV.) 



Long and pointed, teeth fine, base not entire and cordate, 

 nearly smooth, petioles about \ in., with groove above, 



and usually with glands or teeth at base of blade. (Cherries) 



Teeth strongly incurved, trees with dark or reddish bark. 



Teeth fine but very unequal, usually 20 or more to the inch, Prunus 



petiole slender. Pennsylvania 24c 

 Teeth about 15 or less to the inch, leaves large, petiole stout, 



bark dark. Primus serotina 24e 

 Teeth slender, leaves oval or obovate, abruptly tapering, pale 



beneath. Prunus Virginiana 24d 



See also (a low shrub, base wedge-shaped, toothed at apex). Prunus pumila 24b 



Base oblique and entire, petiole short, downy, a small tree, rare. Celtis occidentalis 6la 



Base round or cordate and entire, petiole about ^ in. or longer, without glands. 



Some leaves with irregular lobes, or deeply cut, apex pointed, small trees, southern. 

 Nearly smooth on both sides, length not > 3 in., sharply 



serrate. Pyrus coronaria 28a 



See also (tree escaped from gardens in southern Ontario). Morus alba 63b 



Very downy beneath, and rough to touch above, leaves long. Morus rubra 63a 



Petioles round, without groove, teeth abruptly pointed, slightly glaucous above. 

 Leaves ovate and pointed, teeth fine, veins curving or branching. 



Nearly smooth, a small tree in dry woods, common. Amelanchier 



Uanadensis 30a 

 Very downy, especially when young, in moist soil. Amelanchier 



Botryapium 30b 

 See also (rare shrub of northern swamps, leaves small, 



petioles short). Amelanchier 



oligocarpa 30d 



Leaves oval or rounded, not pointed, base mostly entire, shrubs. 

 Petiole long, veins nearly straight to teeth-points. Amelanchier 



rotundifolia 30c 



Toothed above middle, veins curving, north-western, rare. Amelanchier alnifolia 30e 

 Base mostly acute and entire near petiole, shrubs in moist soil. 



Midrib dotted with dark glands above, teeth fine and much incurved. 



Leaves very downy beneath, nearly smooth above. Pyrus arbidifolia 28b 



Leaves nearly smooth on both sides, mostly obovate. Pyrus melanocarpa 28c 



Densely woolly beneath and on twigs, dark green above. Spircea tomentosa 25b 



Pale and smooth beneath, lower third mostly entire, not taper- pointed. 



Erect and bushy, sharply serrate, petiole | in. or less. Spircea salicifolia 25a 



Mostly low and straggling, petiole ^ in. or more, teeth few. Prunus pumila 24b 



Leaves 2 in. or longer, oval and pointed, twigs finely 



downy. Rhamnus alnifolia 17a 



Glossy green above, veins downy beneath, obovate, leaves 

 and bark bitter, teeth incurved, apex abruptly taper- 

 pointed. Hex verticillata 13a 

 Oblong or oval, nearly entire, petiole slender and often purplish, 



very bitter, apex often mucronate. Nemopanthes 



Canadensis 14a 



