Fibrous-rooted annual climbing or trailing herb; stems angular, rather grey-green, hispid with stiff bristly spreading hairs mainly on the ridges. Leaf-blade ovate- or reniform-cordate in outline, rounded, regularly sinuate-toothed, scabrid hairy above and especially on the nerves beneath, 18–95 mm. long, 27–102 mm. broad, unlobed or shallowly and broadly 3-lobed, with the lobes rounded; petiole roughly spreading-hairy with broad-based pointed hairs, 17–115 mm. long. Male flowers 1–4, on 7–13 mm. long pedicels; receptacle-tube pale green, 3.5–5 mm. long; lobes subulate-filiform, 1.5–4 mm. long; petals yellow with pellucid green veins, 5–10 mm. long, 2.5–5 mm. broad, united below. Female flowers on 5–10 mm. long stalks; ovary ellipsoid, bristly, 9–17 mm. long, 4–8 mm. broad; receptacle-tube green, 3–4 mm. long; lobes subulate, spreading, 2.5–5 mm. long; petals 6–15 mm. long, 3–8.5 mm. broad, rounded and apiculate. Fruit on a stout 8–11 mm. long stalk, ellipsoid, 43–66 mm. long, 28–40 mm. across, densely and softly spiny, with each spine ending in a hyaline bristle, pale green, yellow when ripe. Seed elliptic, rather pointed at each end, 4.5 × 2 × 1 mm.