150 TREES OF THE NORTHERN UNITED STATES 
Genus 86, OSTRYA. 
Slender trees with very hard wood, brownish, furrowed 
bark, and deciduous, alternate, simple, exstipulate, straight- 
veined leaves. Flowers incon- 
spicuous, in catkins. Fruit hop- 
like in appearance, at the ends of 
side shoots of the season, hang- 
ing on through the autumn. 
1. Ostrya Virginica, Willd. (IRoy- 
woop. AMERICAN HoP-HORNBEAM.) 
Leaves oblong-ovate, taper-pointed, 
very sharply doubly serrate, downy be- 
neath, with 11 to 15 straight veins on 
each side of the midrib; buds acute. 
The hop-like fruit 2 to 3 times as long 
as wide; full grown and pendulous, 1 to 
3 in. long, in August, when it adds 
greatly to the beauty of the tree. A 
small, rather slender tree, 30 to 50 ft. 
high, with the bark on old trees some- 
what furrowed; wood white and very 
hard and heavy; common in rich woods. 
and occasionally cultivated. 
O. Virginica. 
2. Ostrya vulgaris, Willd. (Euro- 
PEAN Hop-HORNBEAM.) This species 
from Europe is much like the American 
one, but has longer, more slender, more 
pendulous fruit-clusters. Occasionally 
cultivated. 
O. vulgaris, 
Genus 87. CARPINUS. 
Trees or tall shrubs with alternate, simple, straight- 
veined leaves, and smooth and close gray bark. Flowers 
in drooping catkins, the sterile flowers in dense cylindric 
ones, and the fertile flowers in a loose terminal one form- 
ing an elongated, leafy-bracted cluster with many, sev- 
eral-grooved, small nuts, hanging on the tree till late in 
the autumn. 
