in W. H. Emory, Rep. U.S. Mex. Bound. 2(1): 221. 1859.
Plants often forming open colonies of rosettes, acaulescent or short-caulescent, shorter than 2.5 m. Stems, if present, decumbent, 1–24, aerial or subterranean, simple or sometimes branched, to 2 m. Leaf blade erect, bluish green, concavo-convex, 30–100 × 2–6 cm, rigid, scabrous or glaucous, margins brown. Inflorescences erect, paniculate, dense, arising completely within to mostly extending beyond rosettes, ovoid, 6–8.2 dm, glabrous, rarely slightly pubescent; peduncle scapelike, to 0.8 m. Flowers pendent, 5–13 cm, nearly as wide; perianth campanulate; tepals connate basally to form shallow floral cup 7–12 mm, usually cream-colored, occasionally tinged with purple, 4.5–13 cm; filaments connate proximally into collarlike structure, 3.2–12 mm, fleshy, pubescent; anthers 5–7 mm; pistil 4.5–8 × 0.7–1.2 cm (usually 4–5(–7) times longer than broad); ovary 0.7–1.2 cm; style 5–7 mm; stigmas distinct. Fruits pendent, baccate, indehiscent, elongate, 5–23 × 4–7.5 cm, fleshy, succulent. Seeds dull black, obovate, 7–11 mm diam., 3 mm thick, rugose.
North America, Mexico (Chihuahua, Sonora).
Varieties 2 (2 in the flora).