Perennial herb climbing or trailing to 6 m.; young stems rather shortly and closely crisped-pubescent, sometimes densely so, but sometimes almost glabrous except at the nodes, less often sparsely spreading-hairy or completely glabrous; older stems thickened, woody, up to 15 mm. across, with greyish-brown slightly fissured bark. Leaf-blade ± ovate-cordate or ovate-subtruncate in outline, ± scabrid-punctate above, paler green and subglabrous or sparsely scabrid-hairy to densely cinereous-tomentose beneath, sinuate-toothed, acute to rounded, apiculate and often ± acuminate, 25–110 mm. long, 19–110 mm. broad, sometimes shallowly 3-lobed with large middle lobe and small triangular lateral lobes, rarely palmately 5-lobed with the lobes triangular, or obovate and distinctly narrowed below, sometimes heterophyllous; petiole usually rather shortly and sparsely hairy, 7–85 mm. long. Dioecious. Male flowers 2–60 in sessile or up to 85 mm. pedunculate umbelliform clusters, often with a coaxillary long-pedicellate solitary flower, rarely the inflorescence compound with more than one umbelliform cluster borne at intervals along the peduncle; bracts usually absent; receptacle-tube 2.5–4 mm. long, hairy within; lobes ± subulate, 0.5–0.8 mm. long; petals white, becoming creamy-yellow when old, 1.8–3 mm. long, 1.3–2 mm. broad; stamens 3, on fairly long filaments. Female flowers occasionally solitary, usually 2–16 in sessile or up to 26 mm. pedunculate umbelliform groups, often with a coaxillary solitary flower; pedicels 1–10 mm. long; ovary subglobose to fusiform, sometimes beaked, 3–6 mm. long, 1.5–2.3 mm. across; receptacle-tube campanulate, hairy within, 2–4 mm. long; lobes subulate, ± 0.5 mm. long; petals 2–2.5 mm. long, 1–1.5 mm. broad. Fruits solitary or more often in sessile or pedunculate axillary clusters of up to 10 (rarely more), with 2–20 mm. long pedicels, baccate, sphaeroid, rounded or more rarely slightly apiculate, 6–12 mm. long, 5–11 mm. across, scarlet, ± scrobiculate when dry. Seeds ovate in outline, smooth, compressed, lenticular, 2.2–4 × 1.3–2.5 × 0.5–0.8 mm. Fig. 21/1–8, p. 120.