Leaves linear to cultrate, narrowly lanceolate to lanceolate, entire, inferior surface glabrous-except for the mucilage glands-or rarely pilose (subsp. pseudoangolense).
Capsule narrowly oblong in lateral view, c. 10–25 x 4–6 mm., 4–sulcate, glabrous or pilose, rostrate at the apex (TAB. 23 figs. B1–3).
Flowers obliquely campanulate, corolla 2–5 cm. long, purple, mauve, pink or white; calyx persistent.
Seeds compressed, with a broad double fringe, black or brown when mature (TAB. 24 fig. B1–4).
Annual or perennial, erect or sometimes ascending herb; stem simple or branched.