366 The Ohio Naturalist. [Vol. V, No. 8, 



28. Leaves with short petioles or nearly sessile ; or if with rather prom- 



inent petioles then the twigs clustered and the internodes ver_y 

 unequal. 29. 



29. Internodes very unequal, the leaves crowded at the tip of the twig 



and the twigs clustered. Aza'ea. 



29. Internodes rather uniform, the lea^ es not crowded at the tip and 



the twigs not clustered. 30. 



30. Older twigs finely white speckled or granulated and blistered: 



corolla cylirdric subglobose or urceolaie. Vaccirium. 

 30. Twigs not white speckled or granulated, prominently self-pruned; 

 corolla open-campanulate. Polycodium. 



30. Twigs Avith decurrent ridges from the sides of the petiole base; 



leaves lanceolate; petiole jointed. Lycium, 



—31— 



31. Lateral veins from the midrib straight and parallel or nearly so; 



some or all lateral veins usuallv ending in the serrations, teeth or 

 lobes. 32. 



31. Lateral veins not straight and parallel 43. 



32. Leaves not 2-ranked. 33. 



32. Leaves quite regularlv 2-ranked, that is with the third leaf over the 



first. 36. 



33. Pith 3-angled, buds stalked. Alnus. 

 33. Pith 5-angled, buds not stalked. 34. 



33. Pith cylindrical or nearly so. 35. 



34. Leaves or their lobes bristle-tipped, or if not bristle-tipped then the 



teeth or lobes not sharply acuminate ; buds clustered at the tip of 

 the twig; nut in a cup-like involucre of numerous scales. 



Quercus. 



34. Leaves with sharply acuminate teeth; buds not clustered at the tip! 



nuts with a prickly or spiny involucre. Castanea. 



35. Usually with prominent and typical lateral thorns; carpels of the 



pome bony. Crataegus. 

 35. Without thorns but sometimes with thorn-like stunted branches; 

 leaves irregularly dentate, serrate, or crenate-dentate; sometimes 

 lobed ; pome fleshy without grit cells ; carpels papery or leathery. 



Malus. 



35. Without thorns; leaves serrate or serrate-dentate; pome berry-like, 



carpels not bony. Amelanchier. 



36. Leaves decidedly inequilateral at the base. 37. 



36. Leaves not inequilateral or only very slightly so. 38. 



37. Leaves doubly serrate; axillary buds sessile. Ulmus. 



37. Leaves repand dentate; axillary buds prominently stalked. 



Hamamelis. 



38. Lateral veins ending in the large dentations or serrations which are 



always simple (a vein for each). 39. 



38. Leaves doubly serrate or sometimes simply serrate, the lateral 



veins ending in the main serrations or teeth but not in the 

 smaller ones, or the veins not ending in the serrations. 40. 



39. Leaves ovate or ovate-oblong, short acuminate; teeth not with 



slender points; bark smooth, light-gray. Fagus. 



39. Leaves oblong-lanceolate, acuminate, with slender often inwardly 



curved points on the serrations; bark rough. Castanea. 



40. Lateral veins not ending in the serrations or teeth. Amelanchier. 



40. Lateral veins ending in some of the serrations, teeth or lobes. 41. 



41. Bark .smooth, the trunk and larger branches with fluted or project- 



ing ridges; leaves acute or acuminate, sharply doubly serrate. 



Carpinus. 

 41. Trunk and larger l)ranches not with fluted or projecting ridges. 42. 



