276 CYPERACEAE. 
14. RYNCHOSPORA Vahl, Enum. 2: 229. 1806. 
Leafy sedges, mostly perennial by rootstocks, with erect 3-angled or terete culms, nar- 
row flat or involute leaves, and ovoid oblong or fusiform, variously clustered spikelets. 
Scales thin, 1-nerved, imbricated all around, usually mucronate by the excurrent midvein, 
the lower empty. Upper flowers imperfect, the lower perfect. Perianth of 1-20 (mostly 6) 
upwardly or downwardly barbed or scabrous bristles, wanting in some species (no. 2). Sta- 
mens commonly 3. Style 2-cleft, 2-toothed or rarely entire. Achene lenticular or swollen, 
not 3-angled, smooth or transversely wrinkled, capped by the persistent base of the style 
(tubercle), or in some species by the wholestyle. [Greek, referring to the beak-like tubercle. ] 
About 200 species, of wide geographic distribution, most abundant in warm regions. Besides 
the following, some 27 others occur in the southern United States. 
Style entire or 2-toothed, persistent as a long-exserted subulate beak. 1. R. corniculata. 
Style deeply 2-cleft, only its base persistent as a tubercle. 
Bristles minute or wanting. 
Bristles plumose. 
Bristles downwardly barbed or rarely smooth. 
2. R. pallida. 
3 
Scales white or nearly so; bristles 9-15. 4. R. alba. 
se 
R. oligantha. 
Scales brown; bristles 6. 
Leaves filiform; achene oblong. 
Leaves narrowly linear, flat; achene obovate. 
Bristles equalling the achene; tubercle one-half as long or less. 6. R. Anieskernti. 
Bristles reaching or exceeding the end of the tubercle, which is as long as the achene. 
Spikelets few-several in numerous rather loose clusters. 7. R. glomerata. 
Spikelets very numerous in 2-6 very dense globose heads. 8. 2. axillaris. 
Bristles upwardly barbed. 
R. capillacea. 
Spikelets very numerous in 2-6 very dense globose heads. 8. R. axillaris. 
Spikelets few-several in rather loose clusters. 
Achene smooth. 
Leaves setaceous; achene obovate, shining. g. R. fusca. 
Leaves narrowly linear, flat; achene broadly oval, dull. 10. R&R. gracilenta. 
Achene transversely wrinkled. 
Spikelets ovoid, in erect cymose clusters; achene longer than the bristles. 
Leaves flat; spikelets nearly or quite sessile. 11. RR. cymosa, 
Leaves involute; spikelets distinctly pedicelled. 12. R. Torreyana,. 
Spikelets spindle-shaped, in drooping panicles; achene shorter than the bristles. 
13. R. tnexpansa. 
1. Rynchospora corniculata (lam.) A. Gray. Horned Rush. (Fig. 648.) 
Schoenus corniculatus Lam, Tabl. Encyel. 1:137. 1791. 
Rhynchospora corniculata A. Gray, Ann. Lye. N. Y. 3: 
205. 1835. 
Culm obtusely triangular, stout or rather slender, 
smooth, 3°-7° tall. Leaves flat, broadly linear, 
6/-18/ long, 3/’-8’” wide, rough-margined; umbels 
terminal aud axillary, sometimes 1° broad, usually 
compound; spikelets spindle-shaped, 4’’-6’ long 
in flower, capitate at the ends of the rays and ray- 
lets; primary rays slender, sometimes 6’ long; 
scales lanceolate, thin, acute, light brown; bristles 
about 6, subulate or filiform, rigid, upwardly 
scabrous, shorter than, equalling or exceed- 
ing the achene; style subulate, entire or min- 
utely 2-toothed at the apex, 2-4 times longer 
than the achene, upwardly scabrous, %4/-1’ long, 
persistent and much exserted beyond the scales 
when mature; achene obovate, flat on both sides, 
2’/ long, dark brown, smooth, its surface minutely 
cellular-reticulated. 
In swamps, Delaware to Florida, west to Ohio, Mis- 
souri and Texas. July-Sept. 
Rhynchospora corniculata macrostachya (Torr.) Britton, Trans. N. Y. Acad. Sci. 11: 84. 1892. 
Rhynchospora macrostachya Torr. Ann. Lye. N. Y. 3: 206. 1835. 
Bristles about twice as long as the achene. Range of the type, but extending north to Massa- 
chusetts and Rhode Island. : 
