210 



Cyperaceae 



1. Eleocharis fistulosa Link ex Spreng. Scirpus acut- 

 angulus Roxb.; E. acutangula (Roxb.) Schult; S. fistulosui 

 Poir., non Forsk. ^Misumi-i. Rhizomes sometimes elon- 

 gate; culms soft, acutely 3-angled, 40-80 cm. tall, 2.5-4 mm. 

 thick, smooth, the uppermost sheath 5-10 cm. long, partially 

 reddish brown; spikelets 2-3 cm. long, 3-4 mm. thick, cylin- 

 dric, rather acute, glaucous-green; scales appressed, broadly 

 ovate, 4-5 mm. long, very obmse; achenes broadly obovate, 

 1.5-2 mm. long, light yellow, lustrous, biconvex, the brisdes 6, 

 retrorsely scabrous, slightly exceeding the style base; stigmas 3. 



Shallow water on edge of ponds; Honshu (Kii Prov.), 



Kyushu; rare. Ryukyus, Formosa, China, India, and Aus- 

 tralia. 



2. Eleocharis dulcis (Burm. f.) Trin. Cyperus dulcis 

 Rumph.; Andropogon dulce Burm. f.; Scirpus plantaginoides 

 Rottb.; E. plantaginea (Retz.) Roem. & Schult.; S. planta- 



gineus Retz. Inu-kuro-guwai, Shiro-guwai. Rhizomes 



elongate, usually terminated by a tuber; culms terete, 40-80 

 cm. long, 2-5 mm. thick, glaucous-green, smooth, septate- 

 nodose within, the sheaths 5-20 cm. long, frequendy partially 

 reddish; spikelets cylindric, 4 cm. long, 3-4 mm. thick; scales 

 broadly elliptic, 5-6 mm. long; achenes obovate-orbicular, 2 

 mm. long, tawny, lustrous, smooth, the brisdes with short 

 spines at tip, the spinulae shorter toward apex, the style-base 

 short-deltoid, with a strongly depressed inconspicuous basal 



disc. July-Oct. Shallow water; Honshu (s. part of Kinki 



Distr.), Kyushu; rare. Ryukyus, Formosa, China, India, 



and Malaysia. 



3. Eleocharis kuroguwai Ohwi. Scirpus plantagineus 

 sensu Fr. & Sav. non Retz.; E. plantaginea sensu auct. Japon., 

 pro parte Kuro-guwai. Resembles the preceding; spike- 

 lets cylindric, 2-A cm. long, 3-4 mm. thick, pale green; scales 

 narrowly oblong, obtuse, 6-8 mm. long; achenes 2 mm. long, 

 very abruptly contracted at apex and with a prominent apical 

 discoid tubercle, the bristles spinulose at tip, with spinulae 

 longer toward the apex; anther connective with a linear mucro 



at apex. July-Oct. Ponds and ditches; Honshu (Kanto, 



Hokuriku Distr. and westw.), Shikoku, Kyushu. Korea. 



4. Eleocharis margaritacea (Hult.) Miyabe & Kudo. 

 Scirpus margaritaceus Hult. Shiromi-no-hari-i. Rhi- 

 zomes short; culms slightiy tufted, 25-50 cm. long, sulcate, 

 slender, the upper sheaths 3-10 cm. long, stramineous; spike- 

 lets narrowly ovoid to broadly lanceolate, 7-12 mm. long, 3-4 

 mm. thick, acute to acuminate, dark golden-brown, lustrous; 

 scales narrowly ovate, 5-6 mm. long; achenes obovate, obtusely 

 3-angled, 3 mm. long, white, narrowed at base, puncticulate, 

 with an annular apical disc, the style-base depressed-trigonous, 

 the bristles 6, longer than the achene, retrorsely scabrous; 



stigmas 3. June-July. Moors; Hokkaido (Sarobetsu, Ha- 



matombetsu), Honshu (Rikuchu Prov.), Yanagisawa; rare. 

 s. Kuriles and Kamchatka. 



5. Eleocharis parvula (Roem. & Schult.) Link. Scirpus 



parvulus Roem. & Schult.; S. pollicaris Delile Chabo-i. 



Rhizomes extremely slender, terminated by a small tuber; 

 culms soft, slender, 3-5 cm. long, light green, the sheaths thin- 

 membranous, soon withering, inconspicuous; spikelets ovoid 

 to oblong, 3 mm. long, compressed, light green, few-flowered; 

 scales ovate, hyaline, lustrous, 1.5 mm. long; achenes obovoid, 

 about 1 mm. long, stramineous, smooth, with an indistinct 

 apical annular disc, the bristles 4, slender, slighdy longer or 

 shorter than the achene, minutely retrorsely scabrous. Shi- 

 koku and Kyushu. Europe, Siberia, and N. Africa. 



6. Eleocharis acicularis (L.) Roem. & Schult. var. 

 longiseta Svenson. E. acicularis sensu auct. Japon., non Roem. 

 & Schult.; Scirpus yo\oscensis Fr. & Sav.; E. svensonii Zinserl. 



^Matsuba-i. Rhizomes nearly absent; culms filiform to 



capillary, 3-10 cm. long, sulcate, deep green, the sheaths 2-10 

 mm. long, often partially reddish; spikelets few-flowered, nar- 

 rowly ovoid to broadly lanceolate, 2-4 mm. long, compressed, 

 acute, pale green and usually pardy sanguineous; scales nar- 

 rowly ovate, hyaline; achenes narrowly obovate, I mm. long, 

 raised-reticulate with several longitudinal ribs and very many 

 transverse lines, the style base depressed, triangular, conical, 



the bristles 3-4, unequal, much longer than the achene. 



June-Sept. Common in wet places especially in paddy fields; 

 Hokkaido, Honshu, Shikoku, Kyushu. e. Siberia, Man- 

 churia, Korea, China, Ryukyus, and Formosa. The typical 



phase, with 1-3 brisdes shorter than the achene, occurs in the 

 Ryukyus, China, Korea, Manchuria, e. Siberia, and N. Amer- 

 ica. 



7. Eleocharis tetraquetra Nees var. tetraquetra. E. 



erythrochlamys Miq. ^Ma-shikaku-i. Rhizomes short; 



culms 30-50 cm. long, firm, acutely 4-angled, 1-2 mm. thick; 

 sheaths often somewhat reddish; spikelets narrowly ovoid to 

 broadly lanceolate, 8-17 mm. long, 3-5 mm. thick, often 

 slightly bent, densely many-flowered, ferrugineous; scales ob- 

 long, obtuse, dull, 3-4 mm. long; achenes obovate, 1.5-2 mm. 

 long, compressed-trigonous, tawny, nearly smooth, the style 

 base compressed, trigonous, spongy, rather large, the bristles 6, 

 firm, erect, densely retrorsely spinulose, with spinulae 1 to 2 



times as wide as the bristle. June-Oct. Honshu (ChQ- 



goku), Shikoku, Kyushu. ^Ryukyus, Formosa, China, India, 



Malaysia, and Australia. 



Var. tsurumachii (Ohwi) Ohwi. E. tsurumachii Ohwi 



Kado-hari-i. Culms slighdy softer, the scales obtuse at 



apex. Honshu (Hitachi Prov.). 



8. Eleocharis wichurae Boecklr. Scirpus hakpnensis Fr. 



& Sav.; E. tetraquetra var. wichurae (Boecklr.) Makino 



Shikaku-i. Resembles the preceding; cukns rather soft, 30- 

 50 cm. long, typically 4-angled, or 3-, 5-, or 6-angled in forms 

 (see below), sometimes rhizomatous; scales rather soft, elliptic 

 or oblong, very obmse, ferrugineous-sanguineous; bristles 6, 

 as long as the style-base, with long, soft, plumose, whitish, 



spreading to slightly recurved hairs. July-Oct. Common 



in wet places in lowlands and mountains; Hokkaido, Honshu, 



Shikoku, Kyushu. Korea, Manchuria, and Ussuri. 



Forma petasata (Maxim.) Hara. Scirpus petasatus Maxim. 



Culms 3-angled. Forma teres Hara. Culms nearly terete 



or 5- or 6-angled. 



Eleocharis X yezoensis Hara. E. tetraquetra var. yezoen- 



sis Hara; E. wichurae var. yezoensis (Hara) Ohwi Hime- 



shikaku-i. Alleged hybrid of E. congesta X E. wichurae. 



Culms short, slender; scales rounded, hyaline. Hokkaido 



(Mount Apoi). 



9. Eleocharis congesta D. Don var. japonica (Miq.) T. 

 Koyama. E. pellucida Presl; E. afflata Steud.; E. japonica 

 Miq.; E. afflata var. japonica (Miq.) C. B. Clarke; Scirpus 



japonicus (Miq.) Fr. & Sav. Hari-i. Culms 5^0 cm. 



long, often densely tufted, green, capillary or filiform, ribbed, 

 0.2-1 mm. wide, the sheaths somewhat reddish; spikelets 

 lanceolate to narrowly ovoid, 3-8 mm. long, 1.5-2.5 mm. 

 thick, sometimes proliferous at base; scales membranous, 

 oblong to elliptic, 1.5-2.5 mm. long, obtuse, reddish; achenes 

 obovoid, 0.7-0.8 mm. long, obtusely 3-angled, yellowish 



