84 Proceed i)ii^s of the Ohio State .leadeniv of Science 



31. Buds sessile; leaves donbl}- serr;itc; bark not scaling 

 off in plates. Ulmus. (2^,). 



31. l>uds sessile; lea^•es serrate; bark scaling- off in plates 



like in the Sycamore. Planera. (24). 



32. Lateral veins ending in the large dentations or serra- 



tions which are always simple (a vein for each). 33. 

 ,^2. 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. 34. 



33. Leaves ovate or ovate-oblong, short acuminate ; teeth 



not with slender points; bark smooth, light-gray. 



Fagus. (20). 



_33. Leaves oblong-lanceolate, acuminate, with slender often 



inw;ardly curved points on the serrations ; bark rough. 



Castanea. (21). 



34. Lateral veins not ending in the serrations or teeth. 



Amelanchier. (40) . 



34. Lateral veins ending in some of the serrations, teeth or 



lobes. 35. 



35. Bark smooth, the trunk and larger branches with fluted 



or projecting ridges; leaves acute or acuminate, sharply 

 doubly serrate; nuts small, in a large-bracted catkin. 



Carpinus. (16). 



.35. Trunk and larger branches not with fluted or projecting 

 ridges. 36. 



,36. Bark of trunk and larger branches separating into papery 

 or leathery sheets ; trees or shrubs with glabrous, 

 pubescent, or glandular-warty twigs. Betula. (18). 



36. Biark of trunk scaly, fine furrowed; twigs pubescent; 



carpellate catkin in fruit appearing like that of the hop. 



Ostrya, (17). 



36. Bark scaling off in plates like in the Sycamore ; fruit 



coriaceous, nut-like. Planera. (24). 



—37— 

 ^y. Leaves 2-ranked. 38. 



37. Leaves not 2-ranked. 39. 



