196 CYPERACEAE 
barbed, much longer than the achene: achenes broadly oval or nearly orbicular, 1.5 mm. 
to nearly 2 mm. long, dark brown, lenticular, dull, smooth ; tubercle narrowly subulate, 
flat, widened at the base, pale, smooth, about as long as the achene. 
In pine-land swamps, New Jersey to Florida and Texas. Summer. 
23. Rynchospora Baldwinii A. Gray. Perennial, bright green. Stems somewhat 
tufted, stout, 6-12 dm. tall, sharply 3-angled : leaves several or numerous at the base of 
the stem, commonly over 1 dm. long; blades 2-7 mm. wide, attenuate, smooth or nearly 
so, more or less glaucous: spikelets ovoid or elliptic-ovoid, 5-6 mm. long, chestnut-col- 
ored, aggregated into 1-3 loosely capitate clusters: perianth-bristles 12-14, upwardly 
barbed, fully as long as the achene: achenes oval or orbicular-oval, minutely granular, 
fully 2 mm. long, excluding the triangular-conie smooth tubercle. 
In low pine lands, North Carolina to Georgia and Florida. Spring to fall. 
24. Rynchospora fascicularis (Michx.) Vahl. Perennial, light green. Stems 
sparingly tufted, 6-12 dm. tall, obscurely 3-angled : leaves several at the base of the stem ; 
blades 1.5-3 mm. broad from a dilated base, or rarely slightly wider, more or less invo- 
lute: spikelets about 2-3 mm. long, acuminate, lanceolate in outline, aggregated in 2-5 
remote sometimes compound clusters: perianth-bristles much shorter than the achene, up- 
wardly barbed : achenes lenticular, oval or orbicular-oval, 2 mm. long excluding the tri- 
angular smooth much flattened tubercle. 
In low pine lands, South Carolina to Florida and Louisiana. Spring to fall. 
25. Rynchospora brachychaéta Sauv. Perennial, pale green. Stems tufted, very 
slender or nearly filiform, spreading or procumbent, 2-4 dm. long: leaves several at the 
base of the stem ; blades involute, thus bristle-like or filiform : spikelets ovoid, about 4-5 
mm. long, usually few together in a small terminal cluster: perianth-bristles 3-6, upwardly 
barbed, much shorter than the achene: achenes lenticular, suborbicular, fully 2 mm. long 
including the triangular tubercle, granular, dark brown, twice or thrice as long as the 
bristles. 
In low pine lands, North Carolina to Florida. Alsoin Cuba. Spring to fall 
26. Rynchospora dodecandra Baldw. Perennial, yellowish green. Stems some- 
what tufted, 5-12 dm. tall, 3-angled: leaves crowded at the base of the stem ; blades 4-10 
mm. wide, rather rigid, smooth : spikelets ovoid, 6-8 mm. long, several in 4-6 rather open 
corymbs : perianth-bristles 6-10, upwardly barbed, shorter than the achene: achenes len- 
ticular, orbicular-obovoid or oval, smooth, 3-4 mm. long excluding the depressed nipple- 
like tubercle which is surrounded by a collar-like base, the body barely twice as long as the 
bristles. [2. megalocarpa A. Gray. ] 
In dry sand, North Carolina to Florida and Mississippi. Spring to fall. 
27. Rynchospora ciliata (Michx.) Vahl. Perennial, light green. Stems not densely 
tufted, 3-8 dm. tall, bluntly 3-angled, smooth: leaves often numerous at the base of the 
stem, mostly less than 1 dm. long; blades broadly linear, 5-8 mm. wide, ciliate, glaucous, 
blunt or merely acute: spikelets narrowly ovoid or lanceolate in outline, 5-6 mm. long, 
usually aggregated into a solitary terminal capitate cluster: perianth-bristles 6, 4 as long 
as the achene : achenes lenticular, cancellate, oval or orbicular-oval, 1.5 mm. long ; tuber- 
cle rather depressed, conic. 
In low pine lands, North Carolina to Florida and Mississippi. Spring to fall. 
28. Rynchospora Grayi Kunth. Perennial, light green. Stems often solitary, 
3-7 dm. tall, relatively slender : leaves several or numerous at the base of the stem ; blades 
narrowly linear, 1.5-3 mm. long, smooth, attenuate: spikelets ovoid, 5-6 mm. long, light 
chestnut-colored, aggregated into usually 2-4 capitate clusters: perianth-bristles 6, as long 
as the achene and tubercle: achenes lenticular, plump, cancellate, obovoid, or broadly ob- 
long, 2-5 mm. long, dark brown; tubercle depressed-conic, overtopped by the bristles. 
In dry pine lands, North Carolina to Florida and Texas. Spring to fall. 
29. Rynchospora Plankii Britton. Perennial, bright green. Stems more or less 
tufted, 1.5-4 dm. tall, slender: leaves mainly basal; blades narrowly linear, attenuate, 
1.5-4 mm. wide, smooth, flat or nearly so: spikelets ovoid, 2.5-3 mm. long, chestnut-colored, 
acute or acuminate, aggregated into 1 or few clusters: perianth-bristles 6, much shorter 
than the achene, often about } as long: achenes obovoid or orbicular-obovoid, about 1.5 
D long, cancellate, brown, each surmounted by a depressed tubercle with a collar-like 
ase. 
On plains and prairies, Arkansas and Texas. Spring and summer. 
30. Rynchospora rariflora Ell. Perennial, bright green. Stems densely tufted, 
2-5 dm. long, sometimes reclining, filiform, smooth: leaves involute-filiform or bristle- 
like, smooth : spikelets elliptic or ovoid, few in 2 or 3 lax filiform-peduncled corymbs: 
perianth-bristles 6, fragile, shorter than the achene : achenes lenticular, obovoid or broadly 
