Stem. - Smooth, twining, and climbing over bushes, eight to twelve feet high. Leaves. - Heart or arrow shaped, pointed, alternate. Flowers. - Greenish or pinkish, in racemes. Calyx. - Five-parted, with colored margins. Corolla. - None. Stamens. - Usually eight. Pistil. - One, with three stigmas. Seed-vessel. - Green, three-angled, winged, conspicuous in autumn.
In early summer this plant, which clambers so perseveringly over the moist thickets which line our country lanes, is comparatively inconspicuous. The racemes of small greenish flowers are not calculated to attract one's attention, and it is late summer or autumn before the thick clusters of greenish fruit composed of the winged seed-vessels arrest one's notice. At this time the vine is very beautiful and striking, and one wonders that it could have escaped detection in the earlier year.