Branches: Short, erect, simple, (3-)15-60(-70) mm high, 3-4 mm in diameter, rarely with short axillary branches at base, completely hidden by the 8-10 leaf-pairs throughout. As Marloth aptly states, the specific name is unsuitable, as the typical plants in nature are often sunken and globular, only becoming columnar in cultivation [4].
Leaves:Sessile, connate at the base, 4-ranked, broader than long, 10-15 mm long, 10-23 mm wide, becoming shorter upwards and forming a short tapering columnar, brownish-green, imbricate, tightly clasping and patelliform, rounded, fleshy, concave on the inner or adaxial surface and convex outwardly, lower face not keeled, tip rounded, rarely mucronate, often with membranous margins with grey-green to brown inflexed (slightly recurved) cilia.
Inflorescences: Flowers are borne in a sessile, capitulum (head) directly on top of the plant (often partly hidden among the upper leaves) 10 mm tall and to 22 mm in diameter, rarely a rounded thyrse more or less hidden by leaves below, densely many flowered.
Flowers: White, creamy-yellow or or tinged with red, sweetly scented. Calyx-lobes (sepals) linear to elliptic-oblong, (1.5)3-4(-5) mm long, obtuse, green to brown translucent, tips green. Corolla slender ampulliform, fused basally for 7-13 mm, white, pale yellow and often tinged red. Petals connate below, narrowly elliptic-oblong, 7-13 mm long, tapering above into a blunt, yellowish, beak 1 mm long. Stigma subsessile. Stamens with yellow to brown anthers. Filaments 1.2 - 2 mm. Anthers yellow or brown. Nectar-glands reddish.