Tuber depressed, 1 1/2–5 in. in diam. Stem twining, slender, growing to 6–10 ft. in length, branching, glabrous. Leaves succulent; petiole 1–3 lin. long; blade 3/4–2 in. long, 1/8–1 1/4 in. broad, linear, oblong, ovate-lanceolate, ovate, or spathulate-ovate or spathulate-oblanceolate, acute or obtuse, mucronulate, varying from cuneate-acute to subtruncately rounded at the base, glabrous, often undulate on the margins. Umbels sessile, one- to many-flowered; bracts 1/2 lin. long, subulate; pedicels 3–5 lin. long, slender, glabrous. Sepals 1 lin. long, lanceolate, acute, glabrous. Corolla slightly curved, sometimes drying nearly or quite straight; tube 7–9 lin. long, inflated-ovoid and about 1/8 in. in diam. at the base, cylindric and about 1 lin. in diam. above, slightly funnel-shaped at the mouth, glabrous outside, with a few minute scattered hairs inside (base of the tube rosy-purple, the rest yellowish, Welwitsch); lobes free, widely spreading, 5–6 lin. long, tapering from a deltoid base to fine hair-like points, with a few minute hairs on the basal part (dull yellowish or greenish, Welwitsch). Outer corona arising 1/4 lin. above the base of the staminal-column, not produced into teeth, but forming 5 truncate pouches alternating with the stamens; inner coronallobes 1/2 lin. long, erect, linear-spathulate, slightly cohering at their tips (always?), the entire corona glabrous (greenish, Welwitsch). Follicles 4–6 in. long, 1/6 in. thick, linear-terete, acuminate into a beak. Seeds 2 lin. long, oblong-ovate, plano-convex, with a thickened margin, glabrous.
