Proceedings of the Ohio State Academy of Science 95 



31. Twigs grayish-brown or reddish, usually zigzag; bark 

 mucilaginous fibrous; buds rather fieshy, usually 

 bright red ; medullary rays prominent when the bark 

 is removed ; the winged fruiting panicle often per- 

 sistent. Tilia. (61). 



31. Twigs glabrous or pubescent, reddish or yellowish- 

 brown; pith 5-angled. Castanea. (21). 



31. Twigs downy, grayish-green; pith white, cylindrical, 



large; bark very fibrous. Broussonetia. (28). 



32. Pith interruptedly di:aphragmed, with cavities, small, 



greenish-white. Celtis. (25). 



32. Pith solid. 33. 



33. Terminal bud naked, elongated, tomentose ; buds promi- 



nently stalked, light gray ; twigs zigzag. 



Hamamelis. (29). 



33. Terminal bud absent, the twig showing a terminal self- 



pruning scar at the morphological tip ; or if present 

 then with scales ; buds not stalked. 34. 



34. Terminal bud present, long pointed ; leaf scar narrow 



contracted between the bundle scars. 



Amelanchier. (40). 



34. Terminal bud absent, or if present then the leaf scar 



oval or semicircular. 35. 



35. Twigs dark reddish-brown, speckled, often zigzag ; buds 



reddish-violet, often superposed or clustered ; leaf 

 scars not oblique but below the lateral bud. 



Cercis. (44). 



35. Twigs dark brown, not speckled ; buds not superposed ; 



leaf scars oblique. 36. 



36. Bark smooth, trunk and large branches with peculiar 



fluted or projecting ridges ; bud scales brown, finely 

 pubescent ; staminate catkins in the bud in winter. 



Carpinus. (16). 



36. Trunk not with fluted or projecting ridges. 37. 



37. Bark of trunk scaling ofif like in the Sycamore ; twigs 



very slender; no catkins. Planera. (24). 

 37. Bark in rough ridges; no catkins; twigs and buds in 



