CYPERACEAE 183 
slender, retrorsely barbed, longer than the achene and tubercle : stigmas 2 : achenes obovoid, 
like those of E. ochreata, but twice as large, 3-4 times the length of the conic acute tubercle. 
In wet soil, Maine to southern Ontario, Pennsylvania, and South Carolina. Summer and fall. 
9. Eleocharis maculósa (Vahl) R. Br. Perennial by slender rootstocks. Scapes 
tufted, 1-3.5 dm. long, slender : spikelet ovoid, 5-12 mm. long, rather blunt, dense, purple- 
brown : scales ovate or oblong-ovate, scarious-margined, rather persistent : perianth-bristles 
7-8, retrorsely scabrous, brown or rusty, as long as the achene : stigmas 2: achenes obovoid, 
about 1 mm. long, chestnut-brown, shining, the tubercle abruptly pointed, pale. 
In wet ground, Texas. Alsoin Central and South America. Spring to fall. 
10. Eleocharis capillàcea Kunth. Annual, diminutive. Scapes tufted, capillary, 
2-5 cm. long, sligntly 4-angled : spikelet linear-cylindric, 2-3 mm. long, with 1-4 achenes, 
deep brown or reddish : scales few, nearly oblong or oblong-lanceolate, the 2 lower mostly 
including the spikelet: perianth-bristles 4-6, about as long as the achene, retrorsely sca- 
brous : stigmas 2: achenes lenticular, about 0.5 mm. long, exclusive of the slender conic 
tubercle, brown. 
About pine-land ponds and in wet sand, North Carolina to Florida. Also in Central and South 
America. Spring to fall. 
11. Eleocharis atropurpürea (Retz) Kunth. Annual with fibrous roots. Scapes 
tufted, very slender, 2-9 cm. high : upper sheath 1-toothed : spikelet ovoid, many-flowered, 
subacute, 3-4 mm. long, 2 mm. in diameter, or less: scales minute, ovate-oblong, persist- 
ent, purple-brown except the midvein and very narrow scarious margins : perianth-bristles 
2-4, fragile, pale, minutely downwardly hispid, about as long as the achene : stigmas 2: 
achenes jet black, shining, 0.5 mm. long, smooth, lenticular ; tubercle conic, minute, de- 
pressed but rather acute, constricted at the base. 
In moist soil. Iowa, Nebraska and eastern Colorado to Central America, east to Florida; widely 
distributed in tropical America. Summer and fall. 
12. Eleocharis capitàta (L.) R. Br. Annual with fibrous roots. Scapes densely 
tufted, nearly terete, almost filiform, 0.5-2.5 dm. tall: upper sheath 1-toothed : spikelet 
ovoid, obtuse, much thicker than the scape, 3-5 mm. long, 2-3 mm. thick, many-flowered : 
scales broadly ovate, obtuse, firm, brown except the greenish midvein, narrowly scarious- 
margined, persistent : perianth-bristles 5-8, slender, downwardly hispid, as long as the 
achene : stigmas 2: achenes obovoid, jet black, smooth, shining, 1 mm. long; tubercle de- 
pressed, apiculate, constricted at the base, very much shorter than the achene. 
In moist soil, Maryland to Indiana, Florida and Texas. Also in the tropics. Summer and fall. 
13. Eleocharis bicolor Chapm. Annual, pale green. Scapes tufted, filiform, 0.3-2 
dm. long, sometimes procumbent, 4-angled : spikelet ovoid, 2-3 mm. long, rather blunt, 
8-12-flowered : scales ovate, obtuse, thin, loosely imbricated, with whitish margins and 
keel: perianth-bristles 3, fugacious : achenes lenticular, obovoid, 0.5 mm. long, papillose, 
about twice as long as the bristles ; tubercle broadly conic, about 3 as long as the body of 
the achene. 
In sandy soil, near the coast, Florida. Summer. 
14. Eleocharis obtüsa Schult. Annual with fibrous roots. Scapes tufted, relatively 
stout, rather deep green, nearly terete, mostly erect, 0.5-5 dm. tall: upper sheath 1- 
toothed : spikelet ovoid or oblong-ovoid, obtuse, many-flowered, 3-13 mm. long, 3-5 mm. 
in diameter : scales thin, obovate, oblong-obovate or oblong-orbicular, obtuse, brown, each 
with a broad green midvein and scarious margins : perianth-bristles 6-8, deciduous, usually 
longer than the achene: stigmas 2: achenes pale brown, shining, lenticular, obovoid-ob- 
long, smooth, 1 mm. long or more; tubercle deltoid, acute, compressed, scarcely con- 
stricted at the base, about } as long as the achene. 
.. In wet soil, New Brunswick to Ontario, British Columbia, Florida, Texas and Oregon.—A form 
with more slender generally decumbent or spreading scapes, smaller fewer-flowered spikelets with 
more spreading scales and a smaller achene, is E. obtusa jejüna Fernald. Summer and fall. 
15. Bleocharis Engelmánnii Steud. Annual, quite similar to the next preceding 
species, but scapes commonly taller, sometimes 5 dm. high. Uppersheath obliquely truncate 
or 1-toothed : spikelet cylindric, obtuse or rather acute, 4-16 mm. long, 2-3 mm. in diameter, 
many -flowered : scales pale brown with a green midvein and narrow scarious margins, ovate, 
obtuse, deciduous: perianth-bristles about 6, not longer than the achene or very short or 
wanting : stigmas 2 : achenes obovoid or cuneate-obovoid, fully 1 mm, long, brown, smooth, 
lenticular ; tubercle broad, low, covering the top of the achene, less than 1 its length. 
In wet soil, Massachusetts to Virginia, Indiana, Arkansas, Texas and California.—The form with- 
out perianth-bristles, or mere rudiments, and generally stouter scapes, is E. Engelmannii detónsa A. Gray. 
Summer and fall. 
16. Eleocharis lanceolata Fernald. Annual, bright green. Scapes tufted, slender 
or nearly filiform, 1-2.5 dm. tall: spikelet lanceolate in outline, 5-9 cm. long, about 2 or 
3 mm. thick, rather acute : scales pale, hyaline except green ribs, acute, rather appressed : 
