Japan Flora: Acaulescent annual; leaves linear, 5- 20 cm. long, 3-4 mm. wide; peduncles numerous, exceeding the leaves, slender, twisted, 4- to 5-ribbed; heads turbinate, 6-10 mm. across; involucral bracts many, spreading, the outer lanceolate, acute, twice as long or much longer than the disc flowers, the inner ovate; receptacle usually glabrous; flowers numerous; floral bracts ovate-cuneate, nearly as long as the flowers, puberulent on the back above; staminate flowers 2.5 mm. long; pisdllate flowers 2.5-3 mm. long, the calyx an oval 3-lobed spathe, white-puberulent on the upper margin, gla­brous outside and pilose inside, the petals 3, free, ovate- lanceolate, narrowed at base, long-pilose inside, the stigmas 3, longer than the style. 

Small stemless annual; leaves few, slenderly linear, 1-4 cm. long, 0.3-1 mm. wide, acuminate; peduncles 1-3, 5-7 cm. long; heads lageniform-turbinate, 3.5-6 mm. long, 2.5-3.5 mm. wide, white, 3- to 6-flowered; involucral bracts pale white, ovate-lanceolate, 3.2-5.5 mm. long, cuspidate, exceeding the flowers; receptacle pilose; floral bracts oblong- elliptic, white, short-puberulent on back above; pistillate flowers 2.7-3 mm. long, the calyx white, thin, orbicular-oval, distinctly 3-Iobed, white-pubescent on the upper margin, gla­brous on both sides, die petals ovate-lanceolate, cuneate and short-stipitate at base, pilose inside, the stigmas 3. Peat bogs            

Honshu, Shikoku, Kyushu; China

var. atrosepalum Satake. Heads few-flowered; receptacle pilose; pistillate calyces blackish.  Honshu (Uzen).

var. monococcon (Nakai) T. Koyama Very slender; receptacle gla­brous; pistillate flowers with unilocular ovary and single stigma. Peaty soil; Hokkaido, Honshu (Yamato Prov.) scarce. Stemless annual; leaves linear, 12-18 cm. long, 3-5 mm. wide, gradually attenuate to a somewhat firm acute tip; peduncles numerous, 15-40 cm. tall, prominently 5- or 6-ribbed, twisted; heads hemisphaerical or turbinate, about 1 cm. across; in­volucral bracts about 12-14, broadly lanceolate to lanceolate, 5-8 mm. long, 2-2.5 mm. wide, 1.5 times longer than the disc flowers or shorter; floral bracts obovate, rather acute, puberu­lent, slightly shorter than the flowers; pistillate flowers with spathelike, 3-lobed, puberulent calyx, the petals 3, free, lan­ceolate, cuneate at base, rather acute and puberulent at apex, glabrous outside, pilose inside. A variable species.

var. sikokianum. Receptacle pilose; floral bracts and calyces rather densely white-puberulent on the upper margin; ovary 3-locular; stigmas 3. Honshu, Shikoku, Kyushu. Korea.

var. lutchuense (Koidz.) Satake. Receptacle quite glabrous; floral bracts and calyces also not bearded; otherwise almost as in the typical variety. Honshu (Shimotsuke Prov.), Kyushu. Ryukyus.

var. piliphorum (Satake) Satake. Receptacle pilose; some flowers with the ovary 2-locular and the stigmas 3. Honshu (NagatoProv.).

var. matsumurae (Nakai) Satakc. Receptacle gla­brous; some pistillate flowers with the ovary 2Jocular and with 2 stigmas. Honshu (Bitchu Prov.).

var. mikawanum (Satake & T. Koyama) T. Koyama. Plants slender, small; receptacle pilose; pistillate flowers with unilocular ovary and single stigma. Honshu (Tsukude Moor, Mikawa Prov.).