1'ki-KS OK Till-: XoKTUKKiV Unitkd Statks 15 



■"id. Lca\'(.-s (k"ci(le(ll\- iiK'(|nil;itcr;il al the l)a>c. M . 



• {<». Leaves not ineciiiilatoral or only very slij^^htly .so. '■'>-. 

 ■".I. Axillary bud.s prominently stalked; leave> repaiid- 



dentate. Hamamelis. (4')). 



• tl. Ilnd> sessile; leaves donhly serrate hark not -^calini.; 



off in plates. IJlmus. iiH). 



■ W. l!nd,> sessile; leaves serate. hark scalint?- otf in i)lates 



like in the Sycamore. Planera. (4!»). 



•■>2. Lateral veins ending in the large dentations or serra- 

 tions which are always simple (a vein for eacji). 83. 



■V2. Leaves douhly serrate or sometimes siniply serrate, 

 the lateral veins ending in the main serratif)ns or 

 teeth but not in the smaller ones, or the veins not 

 ending in the serrations. -U. 



■■{•». Leaves o\ate or ovate-oblong, short- acuminate ; teeth 

 not with slender i)(~)ints: bark smooth, light gray. 



Fagus. ( 54 ) . 



■V.\. Leaves ol)h)iig-]anceolate. acuminate, with slender 

 often in"wardl> curved pcnnts (ui the serrations: 

 bark rough. Castanea. ('>■)). 



• 11. Lateral veins not ending in the serration> or teeth. 



Amelanchier. clo). 



"U. Lateral veins ending in some of the serrations, teeth 

 or lobes. M5. 



•T). Bark smooth, the trunk and larger branches with 

 fluted or projecting ridges; leaves acute or acumi- 

 nate, sharply doubly serrate; nuts small, in a large- 

 bracted catkhi. Carpinus. (57). 



".5. Trunk and larger branche> not with Ihited or i^ro'ect- 

 ing ridges. -Ifi. 



■ U'k l')ark of trunk and larger branches separating into 



l^apery <»r leathery sheets; trees or shrubs with 

 glabrous, pubescent, or glandular warty twigs. 



Betula. '•"^'^^;^ 



3(). Bark of trunk scaly, tine furrriwed; twigs glandular- 

 bristly; carpellate catkin in fruit appearing like 

 that of the hop. Ostrya. (5S). 



".!>. Hark scaling off in plates like in the Sycamore: fruit 

 i-oriacertus, nut like. Planera. (II>> 



