plant 6–18 in. high, branching at the base; stems light glaucous-green, 1 1/4–1 3/4 in. thick, cylindric, with 23–30 vertical series of tubercles tipped with stiff light-brown (darker when young) bristles 2 1/2–3 lin. long; flowers subsessile in the grooves between the tubercles; sepals 1–1 1/4 lin. long, subulate-acuminate from a broadly ovate base, glabrous; corolla about 10 lin. in diam., rotate, lobed to less than half-way down, with a very prominent raised ring forming a cup enclosing the corona on the disk, otherwise without a distinct tube, smooth and glabrous on the back, densely covered with conical papillæ all over the very dark purple-brown inner surface, except at the bottom of the cup around the corona, most of them with a minute hair directed at a right angle from their apex; lobes 2 1/2 lin. long, 4–4 1/2 lin. broad, very spreading, very broadly deltoid-ovate, shortly cuspidate-acute, with recurved margins; outer corona large, nearly 2 lin. high, rising almost to the level of the rim of the cup, glabrous, very dark purple-brown, cup-like at the base, with 5 rather broad lobes, divided above their erect concave basal part into two sublanceolate diverging and obliquely recurved-spreading teeth 2/3 lin. long and 1/3 lin. broad; inner corona-lobes about 1/2 lin. long, linear or deltoid-linear, obtuse, dark-purple brown, closely incumbent on the backs of the anthers and equalling or slightly exceeding and incurved over their tips. null
