Climber or trailer to 4 m.; stems annual, herbaceous, pubescent or puberulous, rooting at the nodes when prostrate. Leaf-blade ovate to ovate-orbicular in outline, weakly cordate, sinuate-toothed, green and ± scabrid above, greenish- or brownish-white-tomentose beneath, 39–173 mm. long, 49–170 mm. broad, palmately 5-lobed; lobes ovate and narrowed below, or ovate to triangular and broadest at the base, sometimes very rounded and almost obsolete; petiole 18–140 mm. long, shortly puberulous to rather long-hairy, rather obscurely biglandular at the apex. Tendrils bifid. Dioecious. Male flowers solitary, on 44–160 mm. long pedicels, or in 2–5-flowered racemes, on 55–310 mm. long peduncles and with 10–55 mm. long pedicels; peduncle and pedicels ± long-hairy; receptacle-tube infundibuliform-cylindrical, obscurely 10-ribbed, sometimes slightly bulbous at the base, slightly narrowed above, puberulous and also usually ± densely hairy with longer fine crisped or adpressed hairs, 23–36 mm. long; lobes triangular-subulate, spreading, rather thick and fleshy, 1.5–12 mm. long, sometimes toothed at the margins; petals white with green nerves below, opening in the evenings, rounded, clawed, 23–45 mm. long, 18–35 mm. broad; anthers elongate-oblong, included, free or coherent in centre of the flower; thecae triplicate and much contorted. Female flowers (fig. 6/4, p. 48) on 35–79 mm. long stalks, ± 80 mm. in diameter, subtended by a spathulate bract ± 12 mm. long; ovary ellipsoid, densely white-hairy, 15–29 mm. long, 10–20 mm. across; receptacle-tube 5-angled, flared, 1–3 mm. long; lobes subulate, 2–3 mm. long; petals ± 26–30 mm. long and 24 mm. broad. Fruit on a 63–113 mm. long stalk, ellipsoid or subglobose, 67–230 mm. long, 45–180 mm. across, becoming glabrous, green with white or yellow flecks, hard-shelled, fleshy. Seeds (fig. 6/8, p. 48) pale buff, oblong-pyriform in outline, compressed, tapered to one end, blunt and slightly 2-horned on the shoulders at the other, with 2 flat ridges on the faces running from the horns at one end and meeting at the other, 13 × 6 × 2.5 mm. Fig. 6/1, p. 48.
