CYPERACEAE 193 
++ Spikelets 5-10-flowered. 39. R. prolifera. 
** Tubercle not setose. 
Tubercle conic or triangular, acute, 144-4 as long as the 
achene. 
Achene about 2 mm. long. 40. R. punctata. 
Achene 1-1.25 mm. long. 
Perianth-bristles not longer than the achene or but 
little longer. 
e 
Spikelets clustered : tubercle bluntish. 41. R. microcarpa. 
Spikelets filiform-pedicelled: tubercle sharp- 
inted. 42. R. decurrens. 
Perianth-bristles as long as the achene and tuber- 
cle or longer. 43. R. schoenoides. 
Tubercle depressed, rounded, less than 14 as long as the 
achene. 44. R. miliacea. 
b. Achene constricted at the base into a stipe : tubercle setose. 45. R. stipitata. 
B. Spikelets fusiform to lanceolate, 4-6 mm. long. 
Leaf-blades filiform : achene obovoid : tubercle smooth. 46. R. stenophylla. 
Leaf-blades not filiform: achene linear-oblong or oblanceo- 
late: tubercle setose. 47. R. inexpansa. 
1. Rynchospora Tràcyi Britton. Perennial, bright green. Stems tufted, 5-12 dm. 
tall, nearly terete: leaves elongated ; blades channeled, 4-8 mm. wide, straight, erect or 
ascending: spikelets densely aggregated into 1-6 globose heads 1-2 cm. in diameter, lan- 
ceolate in outline, 5-6 mm. long, acuminate, pale: scales often 9, the fourth one fer- 
tile: perianth-bristles 6, very slender: achenes flat, obovoid or cuneate-obovoid, 2.5 
mm. long excluding the tubercle, minutely wrinkled, ciliate, surpassed by the bristles : 
tubercle subulate, fully twice as long as the achene. — [ Ceratoschoenus capitatus Chapm., not 
È. capitata R. & S.] 
In pine-land ponds, Georgia and Florida to Mississippi. Spring to fall. 
2. Rynchospora solitària R. M. Harper. Perennial or perhaps annual, light green. 
Stems solitary, 6-8 dm. tall, flattened: leaves few; blades about 2 mm. wide, the lower 
ones about J as long as the stem ; upper stem-leaves 1 or 2: spikelets narrowly lanceolate, 
5-6 mm. long, 1-flowered, aggregated into a single dense terminal head 12-15 mm. in 
diameter: bracts filiform, slightly exceeding the inflorescence: perianth-bristles 6, fragile, 
equalling the achene, upwardly barbed: achenes obovoid, plump, 1.5 mm. long, faintly 
pitted, not ciliate, capped by a triangular tubercle of about 3 its length. 
In moist pine lands, southern Georgia. Summer and fall. 
3. Rynchospora Indianolénsis Small. Perennial, bright green. Stems 3-angled, 
5-12 dm. tall: leaves sheathing the base of the stem ; blades 4-8 mm. broad, with smooth 
margins: spikelets rather numerous, about 1 cm. long, aggregated into several dense 
panicled clusters 2-3 cm. broad: scales oval, broadly acuminate, deciduous : perianth- 
bristles surpassing the achene, persistent: achenes flattened and with impressed sides, about 
4 mm. long, each capped by a tubercle nearly 5 mm. long. 
On damp prairies, Indianola, Texas. Spring. 
4. Rynchospora corniculàta (Lam.) A. Gray. Perennial. Stems smooth, 1-2 mm. 
tall: leaf-blades flat, 1.5-4.5 dm. long, 6-16 mm. wide, rough-margined : umbels some- 
times 2-5 dm. broad: spikelets spindle-shaped, much over 1 em. long when mature, 
clustered at the ends of the rays and raylets: primary rays sometimes 15 cm. long: scales 
lanceolate, thin, acute, light brown: perianth-bristles about 6, rigid, upwardly scabrous : 
style subulate from a broad base 2-4 times longer than the achene, upwardly scabrous, 
1-2.5 em. long, much exserted beyond the scales when mature : achenes obovoid, flat, 4 mm. 
long, dark brown, smooth. 
. In swamps, Delaware to Florida, Ohio, Missouri and Texas. Summer and fall.—A variety with 
perianth-bristles about twice as long as the achene and congested inflorescence is R. corniculata macro- 
stáchya (Torr.) Britton ; it extends north as far as Massachusetts. 
5. Rynchospora pusílla M. A. Curtis. Perennial, bright green. Stems densely 
tufted, 0.5-3 dm. tall, filiform : leaves resembling the stems but more slender and curved : 
spikelets in 1-3 separate clusters, elliptic-ovoid, about 2 mm. long, often 3-flowered : scales 
broadly ovate to suborbicular: perianth-bristles wanting: achenes whitish, flat, lenticular, 
oblong-obovoid or cuneate-obovoid, about 1 mm. long, transversely wrinkled, not pinched 
at the base, each with an almost free tubercle. 
About pine-land swamps, Florida to Texas. Alsointhe West Indies. Spring and summer. 
6. Rynchospora divérgens M. A. Curtis. Perennial, bright green. Stems densely 
tufted, filiform or wiry, 1-4 dm. tall : leaves resembling the stems but more slender, curved : 
spikelets elliptic to ovoid-elliptic, 3-3.5 mm. long, acute, in loose or rarely somewhat con- 
tracted corymbs: scales broadly elliptic or broadly ovate: perianth-bristles wanting : 
13 
