Order 113.— ULMACE^E. 633 



1 IT. Americana L. "White Elm. (Fig. 437.) Lvs. ovate, acuminate, serrate, 

 often doubly so, unequal at base; fls. pediceled in loose clusters; fr. ova!, 

 smooth except the densely ciliate margin, its 2 beaks with points incurved ai.d 

 meeting. — U. S. and Can. A majestic tree, usually distinguished by its long pen- 

 dulous branches. The trunk attains a diameter of 3 to 5f, loosing itself suddenly 

 at top in 2 or more primary branches. These ascend, gradually spreading, and 

 repeatedly dividing in broad, graceful curves, and affording a good example of Che 

 solvent axis (§ 174). It is a great favo'rito as a shade tree, and is frequently se: n 

 rearing its stately form and casting its deep shade over the " sweet homes" of N. 

 Eng. April. 



2 TJ. racemosa Thomas. Cork Ehi. Branchlets downy, often witli thick, corky 

 ridges; lvs. ovate, acuminate, auriculaie on one side; fls. in racemes ; pedicels in dis- 

 tinct fascicles, united at their base, fruit ovate, elliptic, ciliate. — A tree found in 

 low grounds, Meriden, N. II. to N. Y., and westward. The twigs and branches 

 are remarkably distinguished by their numerous, cork}', wing-like excrescences. 

 Leaves 3 — 4' long, § as wide, produced into a rounded auricle en one side, doubly 

 serrate, smooth above, veins and under surfaeo minutely pubescent. Flowers 

 pedicellate, 2 — 4 in each of the fascicles which are arranged in racemes. Calyx 

 7 — 8-cleft Stamens 7 — 10. Stigmas recurved. Samara pubescent, the margin 

 doubly fringed. Apr. — Much l;ko Xo. 1, except its inflorescence and bark. 



3 TJ. alata Mx. Wixged Erat. Wiiahoo. Branches smooth, here and there 

 winged with 2 corky ridges ; lvs. oblong-lanceolate, small, acute, doubly serrate, all 

 slightly unequal at base ; lis. in racemes; cal. lobes obovate, obtuse ; fruit downy 

 all over, ciliate-fringed on the margin, beaks slender. — Common in the S. States. 

 Tree with its branches moro regularly cork-winged than in No. 2, its leaves much 

 smaller (18 to 30'' long) and subequal at base, the- petioles only 1" long. (Fruit 

 misrepresented in Michaux.) 



4 TJ. fiilva L. Slippery Elm. Red Elm. Branches rough ; lvs. oblong-ovate, 

 acuminate, nearly equal at base, unequally serrate, pubescent both sides, very 

 rough; buds covered with fulvous down; fls. sessilo; fr. nearly orbicular, scarcely 

 ciliate. — "Woods and low grounds, N. Eng. to Car. The Slippery Elm is much 

 sought on account of the mucilage in tho inner bark. Its diameter is 1 to 2f 

 and height 20 to 40f. The lvs. are larger, thicker and rougher than those of tho 

 White Elm, and exhale a pleasant odor. Fls. collected at the ends of tho young 

 shoots. CaL downy, sessile. Stam. short, reddish, 7 in number. Apr. 



5 U. campestris L. English Elm. Lvs. (small) ovate, doubly serrate, une- 

 qual at base ; fls. subsessile, densely clustered ; sta. 5 — 8 ; cal. segments rounded, 

 cbtuse; samara suborbicular, the border destitute of a fringe of hairs. — From 

 Europe. Introduced and naturalized in tho Eastern States to a small extent It 

 is a majestic tree, 50 — 70f high. Tho main trunk is usually excurrent (i$ 173). 

 Branches rigid and thrown off at a largo angle, foliago dense. In form it favors 

 the Oak more than our native Elms. Many trees of this kind, in tho vicinity of 

 Boston, are particularly remarked in Emerson's Report, pp. 301, 302. 



6 17. montana L. Scotch Elm. Wych Elm. Lvs. (large), obovaie, cuspi- 

 date, doubly and coarsely serrate, cuneato and unequal at base, very scabrous 

 above, evenly downy beneath ; fr. subumbellate, rhombic-oblong ; scarcely cloven, 

 not ciliate. — Another European Elm often planted in our parks. It is a large tree, 

 rather resembling our Slippery Elm than the White Elm. 



7 TJ. crassifolia Nutt. With very small (1' long), thick, oval, obtuso lvs. 

 grows in W. La., probably not E. of tho Miss. It flowers in Sept. only. (Hale.) 



2. PLA'NERA, Gmel. (In honor of John J. Planer, a German bota- 

 nist.) Flowers monoecious-polygamous ; calyx campanulate, 4 to 5- 

 cleft ; stamens 4 to 5 ; stigmas 2, oblong, diverging ; fruit 1 -celled, 

 1-seeded, wingless, dry, nut-like, indehisccnt. — Trees with the habit of 

 TJlmus. 

 P. aquatica Gmel. Lvs. small, smooth, ovate, acute, serrate, equal at baso ; fl& 



axillary, in clusters of 2 to 5 ; sig. plumous ; nut roughened with scale-like points. 



— River swamps, N. Car. to Ga. A tree 30 to 40f high. Feb., Mar. 



