Zosteraceae; Scheuchzeriaceae 



125 



ened margins, the ligule obsolete; inflorescence without ap- 

 pendage on margin; seeds oblong, longitudinally striate. 



Hokkaido, Honshu (centr. distr. and northw.).- Korea and 



Manchuria. 



3. Zostera caulescens Miki. Tachi-ama-mo. Rhi- 

 zomes elongate and branched; stems slender; leaves about 14 

 mm. wide, 9(-ll)-nerved, abruptly acute to rounded and 

 mucronate at apex, smooth, the ligule obsolete; inflorescence 

 widiout an appendage on margin; seeds ellipsoidal, about 5 

 mm. long, 3 mm. wide, with about 20 longitudinal indistinct 



striadons. Honshu (Rikuchu, Noto, and elsewhere). 



Korea. 



4. Zostera asiatica Miki. Z. pacifica auct. Japon., non 



S. Wats. O-AMA-MO. Rhizomes elongate; leaves 10-15 



mm. wide, elongate, 9(-Il)-nerved, to 150 cm. long, entire 

 and smooth, subretuse, the ligules not conspicuous; in- 

 florescence not appendaged on margin; seeds oblong, about 5 

 mm. long, 3 mm. wide, obscurely striate. July-Oct. Hok- 

 kaido. Sakhalin, Kuriles, and Korea. 



5. Zostera nana Roth. Z. japotiica Asch. & Graebn. 



Ko-AMA-Mo. Rhizomes slender, elongate; stems slender; 

 leaves 10-40 cm. long, 1.5-2 mm. wide, 3-nerved, smooth and 

 entire, rounded to retuse at apex; seeds oblong, about 2 mm. 



long, lustrous and smooth. Sept.-Nov. Muddy places in 



shallow sea water; Hokkaido, Honshu, Shikoku, Kyushu. 



Eurasia and Africa. 



2. PHYLLOSPADIX Hook. Suga-mo Zoku 



Perennial dioecious herbs growing in saline vv'ater, with thick rhizomes; stems short; leaves flat, ribbonlike, sheathed at base; 

 spadix linear, naked at back, enveloped by a leaflike bract; flowers in 2 rows on one side of spadix, alternate, the perianth not 

 developed; staminate flowers consisting of a sessile 1-locular anther; pistillate flowers consisting of one sessile ovary with a 



short style and two stigmas, the ovule solitary, pendulous, orthotropous; fruit broadly cordate-lobate at base. Several species 



around the Pacific basin. 



I A. Leaves 2-4.5 mm. wide; rhizomes with pale fulvous fibers \. P. iwatensis 



IB. Leaves 1.5-2.5 mm. wide; rhizomes with dense blackish brown fibers 2. P. japonica 



1. Phyllospadix iwatensis Makino. P. scouleri auct. 



fapon., non Hook. Suga-mo. Rhizomes short, caespitose, 



estoloniferous, densely leafy; leaves 20-100 cm. long, 2^.5 

 mm. wide, 3-nerved, rounded at apex, smooth except the 

 upper margins minutely toothed; peduncles (stems) short, 

 solitary, simple, compressed, to 8 cm. tall; pistillate inflores- 

 cence about 4 cm. long, the bracts 2 ranked, narrowly lanceo- 

 late, obtuse at apex; fruit rather numerous, sagittate, about 5 



mm. wide.- -July-Sept. Rocky places in shallow sea water; 



Hokkaido, Honshu (northern distr.). Kuriles and Sakha- 

 lin. 



2. Phyllospadix japonica Makino. ? P. senulatus auct. 

 Japon., non Rupr. Eei-ama-mo. Similar to the preced- 

 ing; leaves narrower, 1.5-2.5 mm. wide, 3-nerved, the basal 



part becoming blackish brown fibers. July-Oct. Honshu, 



Shikoku, Kyushu. ? China. 



Fam. 37. SCHEUCHZERIACEAE Horomui-so Ka Arrowgrass Family 



Marsh herbs; leaves usually radical, linear or cylindric, sheathed at base; flowers small, bisexual, in terminal spikes or 

 racemes; perianth-segments 4-6, biseriate, deciduous or persistent, small, greenish; stamens 3-6, filaments free, short or elongate, 



the anthers usually 2-locular, extrorse; carpels 3-6, each with 1-2 anatropous ovules, the embryo straight. Three genera with 



more than 10 species widely distributed. 



lA. Flowers numerous, ebracteate, in racemes or spikes, on naked peduncles; carpels 3-6, connate 1. Trighchin 



IB. Flowers few, loosely arranged, bracteate, on stems with few bracts; carpels 3, nearly free when mature 2. Scheuchzeria 



1. TRIGLOCfflN L. 



Shiba-na Zoku 



Marsh herbs; leaves radical, linear, semiterete, with a membranous sheath at base; flowers short-pedicelled, racemose or in 

 spikes on leafless scapes, numerous, bractless; perianth-segments 3 or 6, deciduous, the inner whorl inserted a litde above the 

 outer; stamens 3 or 6, the anthers sessile, inserted at base of perianth, dorsifixed; carpels 3-6, l-lcx:ular, connate, each with 1 

 ovule, the stigma sessile; fruit cylindric to obovoid, the mature carpels deciduous from the persistent axis; seeds erect, cylindric 

 to ovoid. About 10 species widely dispersed in temperate and subtropical regions. 



lA. Carpels 3; fruit cylindric, narrowed to the base, on an erect pedicel 1. T. palustre 



IB. Carpels 6; fruit erect, oblong, obtusely rounded at base, on an ascending to curved pedicel 2. T. maritimum 



1. Triglochin palustre L. Hosoba-no-shiba-na, Misa- 

 Ki-s6. Plant stoloniferous; rhizomes short; leaves linear, 

 shorter than the scape, semiterete, soft, 10-25 cm. long, about 

 1 mm. wide, gradually narrowed to an obtuse apex, with a 

 membranous sheath at base, the ligule ovate-rounded, about 

 I mm. long; scapes 20-40 cm. long, erect, the racemes elongate 

 after flowering, to 25 cm. long; flowers loosely arranged, 

 small, on an erect pedicel 4-8 mm. long, the perianth-seg- 

 ments elliptic, concave, 1.5-2 mm. long; fruit 8-10 mm. long, 



about 1.2 mm. wide. June-Aug. Bogs; Hokkaido, Hon- 

 shu, (centr. distr. and northw.). Widely distributed in the 



cooler regions of Eurasia, N. America, and southern S. Amer- 

 ica. 



2. Triglochin maritimum L. Shiba-na. Perennial 

 herb; rhizomes thick and short, caespitose; leaves 10-30 cm. 

 long, linear and rather flat above, obtuse, 1.5-4 mm. wide, 

 mouths of the sheaths protruding into a ligule 3-5 mm. long; 

 scapes 20-40 cm. long, racemes rather densely many-flowered. 



