A shrubby climber with stems 15–20 ft. long; branches unarmed, reddish or reddish-green, young parts pubescent or puberulous. Leaves elliptic or elliptic-ovate, apex abruptly and shortly acute, base cordate, often only slightly, margin crenate-dentate, base 3-nerved, with 3–4 ascending lateral nerves on each side curving to unite within the margin, 3–6 in. long, 2 1/4–3 1/4 in. wide, upper face with appressed short stinging hairs and sparsely pubescent or glabrous, lower face pubescent with short stinging hairs on the veins, cystoliths short, linear, more or less conspicuous on the upper face, closely following the venation, or absent from the lower; petiole 1–1 3/4 in. long, pubescent and with short stinging hairs, or puberulous. Stipules ovate, long-acuminate, 1/4 in. long, pubescent, caducous. Female inflorescence much branched, up to 4 in. long and about 3 1/4 in. broad, branches somewhat flattened, primary spreading, up to 1 1/2 in. long, secondary up to 3/4 in. long, the short tertiary or quaternary branches few-flowered, bearing a tuft of stinging hairs below the short pedicels. Ovary shortly ovoid, about 1/2 lin. long, at first completely enveloped in the sac-like perianth, above which the round ferruginous tufted stigma projects. Achene broadly subcompressed-ovoid, enveloped except at the extreme tip by the fleshy yellow perianth, which is barely 1 lin. long and is frequently split into two valves.
