Japan Flora: Glabrous, delicate annual; stems 8-25 cm. long, slender, striate, simple or with ascending branches; leaves nearly sessile, oblong or elliptic, 3-8 mm. long or the upper lanceolate ones to 12 mm. long, 1.5-4 mm. wide, mucronate, entire or with few spinules on the upper margin; spikes many-flowered, at first short and dense, later elongating, 2-6 cm. long; flowers sessile, rosc-purple, about 2 mm. long; sepals lanceolate, less than 1 mm. long; lateral petals shorter than the lower; capsules less than 2 nun. wide, glabrous, reniform, flat, with a few spines on the margins, the seeds about 0.8 mm. long, ellipsoidal, dull.  Aug.-Sept. Wet places in lowlands.

Honshu, Shikoku, Kyushu; rare. Formosa, s. Korea, India, Malaysia, and Australia.