396 UKTICACE.£. (NETTLE FAMILY.) 



rough downwards ; branchlets downy ; calyx-lobes and stamens 7 - 9 ; fruit 

 (§' — f wide) with the cell pubescent. — Along streams, common from W. New 

 England to Wisconsin and Kentucky. March, April. — A small or middle- 

 sized tree, with tough reddish wood, and a very mucilaginous inner bark. 



* * Flowers on slender drooping peduncles or pedicels, winch are jointed above the 

 middle : fruit ovate or oval, fringed-ciliate : leaves smooth and glabrous above, or 

 nearly so. 



2. U. Aiaei'acaiia, L. (pi. Clayt.), Willd. (American or White 

 Elm.) Buds and branchlets glabrous ; branches not corky ; leaves obovate-oblong 

 or oval, abruptly pointed, sharply and often doubly serrate (2' -4' long), soft- 

 pubescent beneath, or soon glabrous ; flowers in close fascicles ; calyx with 7-9 

 roundish lobes ; fruit glabrous except the margins (i' long), its sharp points in- 

 curved and closing the notch. — Moist woods, especially along rivers, in rich 

 soil ; common. April. — A large and well-known ornamental tree, with spread- 

 ing branches and drooping branchlets. 



3. U. raceilldsa, Thomas. (Corky White Elm.) Bud-scales doicny- 

 ciliate, and somewhat pubescent, as arc the young branchlets ; branches often with 

 corky ridges: leaves nearly as in the last; flowers racemed; fruit much as in the 

 last, but rather larger. — River-banks, W. New England, New York, and Mich- 

 igan. April. — Wood tougher and finer-grained than in the last. 



4. XT. allif&ta, Michx. (Winged Elm. Whahoo.) Bud-scales and 

 branchlets nearly glabrous ; branches corky-ivinged, at least some of them ; leaves 

 ovate-oblong and oblong-lanceolate, acute, thickish, small (l'-2^' long), seldom 

 oblique ; calyx-lobes obovate ; fruit downy on the face, at least when young. — 

 Virginia, Illinois, and southward. March. — Wood fine-grained, valuable. 



U. campestris, L., the English Elm, was early introduced near Boston, 

 &c. 



2. PLAKEBA, Gmel. Planer-Tree. 



Flowers monceciously polygamous. Calyx 4 - 5-clcft. Stamens 4-5. Ovary 

 ovoid, 1-celled, 1-ovuled, crowned with 2 spreading styles which are stigmatose 

 down the inner side, in fruit becoming coriaceous and nut-like, not winged. 

 Albumen none : embryo straight. — Trees with small leaves, like those of Elms, 

 the flowers appearing with them, in small axillary clusters. (Named for J. J. 

 Planer, a German botanist.) 



1. P. aquatica, Gmel. Nearly glabrous; leaves ovate-oblong, small; 

 fruit stalked in the calyx, beset with irregular rough projections. — Wet banks, 

 Kentucky (Michx.) and southward. April. 



3. CELT IS, Tourn. Nettle-tree. Hackberry. 



Flowers monceciously polygamous. Calyx 5 - 6-parted, persistent. Stamens 

 5-6. Ovary 1-celled, with a single suspended ovule: stigmas 2, long and 

 pointed, recurved. Fruit a globular drape. Embryo curved, nearly enclosing 

 a little gelatinous albumen : cotyledons folded and crumpled. — Leaves pointed, 

 petioled. Stipules caducous. Flowers greenish, axillary, the fertile solitary or 



