Sparganiaceae 



119 



pistillate and bracteate; flowers sessile, unisexual, the periantli-segments 3-6, membranous, cuneate; stamens 3 or more, the 

 filaments filiform; ovary solitary, sessile, I- to 2-locular, the ovules solitary in each locule, basal or pendulous, anatropous; style 

 simple or forked; fruit nudike, indehiscent, obovoid or wedge-shaped, with a spongy exocarp; embryo cylindric, the endosperm 

 mealy. A single cosmopolitan genus, with about 20 species. 



1. SPARGANIUM L. Mikuri Zoku 



Perennial swamp or marsh herbs with the characters of the family. 



lA. Stigma filiform, 3-4 mm. long; inflorescence a panicle; stout plants with leaves 7-12 mm. wide 1.5. stolonijcrum 



IB. Stigma linear to narrowly ovate, 2 mm. long or less; inflorescence a spike (if the plant bearing spikes branches below, then the leaves 

 not more than 5 mm. wide). 

 2A. Styles distinct. 



3A. Lower head supra-axillary; spikes always simple. 



4A. Staminate heads usually 1-2, contiguous with the congested pistillate heads 2. 5. glomeratum 



43. Staminate heads 2-9, remote, tlie pistillate heads not congested. 



5A. Leaves slender, 1-4 mm. wide, keeled not at all or only near base, usually floating, the stems often floating. 



3. 5. an giisti folium 

 5B. Leaves 4-10 mm. wide, with a keel at back; stems and majority of leaves aerial. 



6A. Styles with the stigma 3-4 mm. long; fruit fusiform 4. S. simplex 



6B. Styles with the sugma about 2 mm. long, fruit rhombic-ovoid 5. 5. fallax 



3B. Heads all axillary; spikes sometimes branched. 



7A. Fruit obovoid or broadly ovoid, subsessile; leaves 2-5 mm. wide; spikes often branched; pistillate heads sessile. 



8A. Leaves all floating, without a keel, 2-2.5 mm. wide, spikes usually branched 6. 5. gramineum 



8B. Leaves at least partly aerial, keeled beneath, 3-5 mm. wide; spikes sometimes partly branched 7. 5. stenophyllum 



7B. Fruit oblong-fusiform, slightly narrowed at the middle, stipe 1.5-2 mm. long; leaves 4-10 mm. wide, slightly keeled beneath; 



spikes simple; lowest head usually short-peduncled 8. 5. japonicum 



2B. Style very short; slender herb in alpine ponds; leaves slender, floating; lower pistillate heads supra-axillary, the staminate usually 

 solitary 9. S. hyperboreum 



1. Sparganium stoloniferum Hamilt. S. longijolium long. Shallow ponds in high mountains; Honshu (centr. 



sensu auct. Japon., non Turcz.; S. ramosum sensu auct. Japon., distr. northw.). — ■ — Eurasia. 



non Huds.; S. ramosum subsp. stolonijerum (Hamilt.) 3. Sparganium angustifolium MicLx. S. affine 



Graebn.; S. coreantim Lev.; 5. macrocarpiim Makino; 5. Schnizl.; 5. (f/Vera/o/mra sensu Miyabe & Kudo, pro parte, non 



stolonijerum var. macrocarpum (Makino) Hara and var. Graebn. Hosoba-uki-mikuri. Stems elongate, floating or 



coreanum (Lev.) Hara Mikuri, O-mikuri, Kado-h.«i- aerial, 30-50 cm. long, the floating leaves mosdy narrow, 



MIKURI. Soft spongy greenish herb with slender rhizomes; about 4 mm. wide, compressed, keeled beneath; spikes simple; 



stems erect, 0.7-1 m. long, rather stout; leaves flattened, keeled pistillate heads 2-A, 7-10 mm. in diameter, the lower 1 or 2 



on back, linear, elongate, 7-12 mm. wide, slighdy narrowed with a supra-axillary peduncle; staminate heads commonly 



upward to an obtuse apex; panicle 30-50 cm. long, the bracts approximate; fruit short-pedicelled, about 4 mm. long, fusi- 



leafy, the lower ones sometimes exceeding the panicle, the form; stigma hnear, about 1 mm. long. Reported from 



branches few, each with 1-3 pistillate heads in lower part and Hokkaido (Mount Yubari) . Kamchatka, Europe, and N. 



several staminate heads loosely disposed above; pistillate America. 



flowers sessile; style elongate, the stigma filiform; fruit 4. Sparganium simplex Huds. S. affine sensu Miyabe & 



rounded-obovoid, angular, 6-10 mm. long, 4-8 mm. in diame- Miyake, non Schnizl. Ezo-mikuri. Stems usually erect, 



ter, sessile. June-Aug. Shallow water in lowlands; Hok- 20-60 cm. long; leaves elongate, 3-12 mm. wide, erect, keeled 



kaido, Honshu, Shikoku, Kyushu. Korea, China to Turkes- beneath; spikes with 2-5(-6) pistillate, and 3-8 staminate 



tan, and Afghanistan. heads, the lowest head pedunclate; fruit 4-5 mm. long, 2-2.5 



2. Sparganium glomeratum Laest. S. glehnii Meinsh. mm. in diameter, gradually narrowed to a beak; stigma linear, 



Tama-mikuri. Soft greenish herb 30-60 cm. high; 1.5-2 mm. long. Reported from Hokkaido. Eurasia and 



stems usually erect, shorter than the leaves; leaves sometimes N. America. 



floating, the aerial ones compressed, 5-12 mm. wide, slighdy 5. Sparganium fallax Graebn. S. yamatense Makino. 



keeled beneath; spikes 10-20 cm. long, simple, with leafy yA^L'^.To-MIKURI. Stems erect, 40-80 cm. long; leaves 



bracts much longer than the spike; pistillate heads approxi- erect, longer than die stem, 4-8 mm. wide, keeled beneath; 



mate, the lower ones often on short supra-a.xillary peduncles; spikes erect, the lower bracts about as long as the spike, the 



staminate heads 1 or 2, adjacent to the pistillate, inconspicuous; pistillate heads 4-6, relatively wide apart, usually sessile, 2-2.5 



fruit numerous, on pedicels about 1.5 mm. long, narrowly ob- cm. in diameter in fruit, the staminate 4-7, interrupted; fruit 



long-fusiform, about 4 nun. long, 1.5 mm. wide, scarcely rhombic-ovoid or fusiform, (y-l mm. long, about 2 mm. wide, 



angled; style inclusive of stigma about 1.5 mm. long. July- the pedicels 2-3 mm. long. Aug. Shallow ponds in low- 



Aug. Shallow ponds and lake margins; Hokkaido, Honshu lands; Honshu (Kanto Distr. and westw.), Kyushu. Burma 



(mountains of centr. distr. northw.). Eurasia and nw. and India. 



America. 6. Sparganium gramineum Georgi. S. friesii Beurl. 



Var. angustifolium Graebn. Hosoba-taj.ia-mikuri. Plant Uki-mikuri. Submerged stems slender, soft, 30-40 cm. 



much more slender; leaves 2-4 mm. wide; fruit about 3 mm. long; leaves floating, flat, flaccid, 40-50 cm. long, 2-2.5 mm. 



