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barbed awn which usually exceeds the scale, the stalk half as long as the nearly 
sessile achene: bristles slender, tapering to the apex, retrorsely barbed, usually 
longer than the achene. (/. squarrosa, var. pumila Torr.)—A species of the eastern 
United States and extending to Louisiana, but represented within our range by the 
two following varieties: var. BREVISETA Coville, of the Gulf States and eastern 
Texas, has smooth bristles not exceeding the stipe of the achene, and broader per- 
ianth-scales rounded at apex and awnless or with a mere apiculation; var. HISPIDA 
Chapman, of the north Atlantic and Gulf States and extending into Texas, is 4 to 9 
dm. high, with sheaths and frequently the stems and leaves densely hirsute retrorsely 
barbed bristles reaching the middle or apex of the achenium, and rhomboidal or 
deltoid-ovate perianth-scales with a thick short awn or point. 
9. HEMICARPHA Nees. 
Spikelet, flowers, ete., as in Scirpus, except that there is a minute 
translucent scale between the flower and the axis of the spikelet; also 
with only one stamen, 2-cleft style, and no bristles or other perianth. 
Or 
1. H. micrantha Britton. Dwarf annual, 2.5 to 12.5cem. high: involucre 1-leaved, 
as if a continuation of the bristle-like stem, and usually with another minute leaf: 
spikelets 2 or 3, barely 4 mm. long: scales brown, tipped with a short squarrose point, 
(H. subsquarrosa Nees, )—Sandy borders of ponds and rivers, from the Atlantic States 
through Texas to Mexico and the Pacific coast. Var. anisruLATA Coville, from the 
interior of the State, bears sporading awns nearly as long as the scales themselves, 
10. RHYNCHOSPORA Vall. (BEAK-RUSH). 
Chiefly perennials, with more or less triangular and leafy stems, 
terete or sometimes flattish spikelets (ovate, globular, or spindle- 
shaped) panicled or variously clustered, open or barely concave scales 
(lower commonly loosely imbricated and empty, the uppermost often 
subtending imperfect flowers), mostly 6 perianth-bristles (sometimes 
wanting), generally 2 stamens, and a lenticular globular or flat achene 
crowned with a conspicuous tubercle or beak consisting of the persistent 
indurated base or even of the greater part of the style. 
* Style entire or only shortly bifid, never cleft to the middle : inflorescence paniculate. 
1. R. corniculata Gray. Stem 9 to 18 dim. high: leaves about 12 mm. wide: cymes 
decompound, diffuse: spikelets lanceolate, acuminate, with 1 perfect and 1 to 4 
staminate flowers: scales few: bristles rigid, stout, awl-shaped, minutely scabrous 
upward, unequal, shorter than the achene: style filiform and gradually thickened 
downward, in fruit persistent as an exserted slender-awl-shaped upwardly roughened 
beak several times longer than the smooth flat obovate achene.—Extending into 
Texas from the Mississippi Valley and Gulf States. Var. MacrostTaciya Britton 
(R. macrostachya Torr.), of similar but more northeastern range, has often somewhat 
simple and smaller cymes, usually more clustered spikelets, and capillary bristles 
twice the length of the achene. 
2. R.scutellata Griseb. Stem rather stout, 3 to9 dm. high, glabrous: leaves 
linear, flat: spikelets lanceolate (6 to10 mm. long), 3 to 5-tlowered, in corymbose 
clusters of 3 to5 spikelets: scales brown, ovate, acute, fertile ones larger than the 
sterile: bristles slender, unequal, finely barbed upward, equaling or slightly exceed- 
ing the achene, which is brown, ovate or obovate, compressed, slightly concave on 
each face, finely puneticulate, with a rather prominent keel on both edges; beak 
black, compressed, conic, about as long as the achene.—A West Indian species 
found near Indianola. (Ravenel) 
