Stem climbing, 1/4 in. thick, not tubercled. Leaves spreading, 1 1/2–2 1/2 in. distant, glabrous; petioles 4–5 1/4 in. long, sheathing to 1/2–1 1/4 in. from the top; blade 4 1/4–8 in. long, 2–3 1/2 in. broad, unequal-sided, obliquely oblong, shortly cuspidate-acuminate, cuneately rounded into an obtuse base; primary lateral veins 9–11 on each side of the midrib; no glands. Peduncles 3–4 (or more ?) in a short terminal bracteate raceme, 1–1 1/4 in. long, moderately stout. Bracts 1 3/4–2 in. long, 7–9 lin. broad, oblong, acute, with 2 wing-like keels down the back. Spathe about 2 in. long, 1 in. broad, elliptic or elliptic-oblong, obtuse, apiculate, expanded, deeply concave, very shortly convolute at the base, soon falling off. Spadix shorter than the spathe, sessile, clavate; female part 3–4 lin. long, 2–2 1/2 lin. thick; male part about an inch long, about 4 lin. thick near the obtusely rounded apex.
