A spiny succulent leafless bush 1 1/2–6 ft. high, branching at the base. Branches ascending, when young 1/2–1 in. in diam., less when dried, 4–5-angled, usually with distant slight constrictions, sides concave, becoming nearly flat with age, glabrous, light green, slightly glaucous; angles slightly compressed, with the margins even or more or less distinctly sinuate-toothed, sometimes on the same branch and the spine-shields sometimes united into a continuous dark brown or grey horny border, sometimes interrupted at the flowering-eyes. Leaves rudimentary, scale-like, about 3/4 lin. long, ovate, acute. Spines 1/4–3 lin. long, sometimes obsolete, in pairs 1/4– 3/4 in. apart, diverging, with or without a pair of minute prickles or points near their base, dark grey. Flowering-eyes 1–2 1/2 lin. above the spine-pairs. Cymes sessile or subsessile, solitary, with 3 or fewer involucres. Central involucre male, sessile, deciduous, lateral on peduncles (cyme-branches) 1/2–1 lin. long, hermaphrodite, 1 1/2–1 3/4 lin. in diam., somewhat obconic, glabrous, with 5–6 subquadrate or transversely rectangular toothed lobes; glands contiguous or only separated by cut-like notches or united into a continuous rim, when separate 2/3–1 lin. in their greater diam., transversely oblong, entire, yellow. Capsule about 2 lin. in diam., 3-angled or somewhat 3-lobed as seen from above, glabrous, exserted much beyond the involucre on a slender curved pedicel 1/4 in. long; styles 2/3–1 lin. long, shortly united at the base, then spreading, slender, with thickened or subcapitate tips. Seeds smooth.
