38 
ULMACEAE. 
Utmus. Elm. 
(Family Ulmaceae). 
Trees, usually of large size: de- 
ciduous. Twigs rather slender, 
zig-zag, terete: pith small, round- 
ed, continuous. Buds solitary or 
/. collaterally branching, variously 
/ ovoid, obliquely sessile, the termi- 
; nal lacking: scales about half-a- 
dozen, 2-ranked. Leaf-scars alter- 
nate, 2-ranked, broadly crescent- 
' shaped or half round, scarcely 
raised: bundle-traces 3 or com- 
pounded in 3 usually distinct 
groups: stipule-scars unequal. 
References under Aphananthe. 
1. Buds small (1.5 mm.), globose: 
scales 4. (1). U. pumila. 
Buds distinctly larger or with 
more visible scales. 2 
2. Twigs gray-buff, rough: buds 
red-hairy. (2). U. fulva. 
Twigs red-brown, or gray. .3. 
. Buds blackish-red. 4. 
Buds brown. 7. 
. Buds and twigs glabrous. U. laevis. 
’ Buds more or less hairy. 5. 
. Twigs glabrescent: bark rough. 6. 
Twigs hispid: bark of branches smooth. (3). U. glabra. 
. Twigs not corky. U. campestris. 
Twigs often with corky ridges. U. campestris suberosa. 
. Twigs moderately slender. 8. 
Twigs very slender, often corky-winged. (4). U. alata. 
. Twigs not corky. (White elm). : U. americana. 
Twigs often with corky outgrowths. (5). U. racemosa. 
