I$4 FLORA. 



some species by the whole style. [Greek, referring to the beak-like tubercle.] 

 About 200 spe< -it's, of wide geographic distribution, most abundant in warm re- 

 gions. Besides the following, some 27 others occur in the southern U. S. 



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. 2. R. pallida. 



Bristles plumose. 3. R. oligantha. 



Bristles downwardly barbed or rarely smooth. 



Scales white or nearly so ; bristles 9-15. 4. R. alba. 



Scales brown ; bristles 6. 



Leaves filiform ; achene oblong. 5. R. capillacea. 



Leaves narrowly linear, flat ; achene obovate. 



Bristles equalling the achene; tubercle one-half as long or less. 



6. R. Knieskernii, 

 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. glo?nerata. 

 Spikelets very numerous in 2-6 very dense globose heads. 



8. R. axillaris. 

 Bristles upwardly barbed. 



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. 9. R./usca. 



Leaves narrowly linear, flat ; achene broadly oval, dull. 



10. R. gracilenta. ■ 

 Achene transversely wrinkled. 



Spikelets ovoid, in erect cymose clusters ; achene longer than th 

 bristles. 

 Leaves flat ; spikelets nearly or quite sessile. n. R. cytnosa. 

 Leaves involute ; spikelets distinctly pedicelled. 



12. R. Torreyana.- 

 Spikelets spindle-shaped, in drooping panicles ; achene shorter than th 

 bristles. 13. R. inexpansa. ; 



1. Rynchospora corniculata (Lam.) A. Gray. Horned Rush. (I. F. 

 648.) Culm triangular, smooth, 1-2 m. tall. Leaves flat, 1.5-4.5 dm. long, 6 

 16 mm. wide, rough-margined; umbels sometimes 2.5 dm. broad; spikelets spindle 

 shaped, 8-12 mm. long in flower, capitate at the ends of the rays and raylet: 

 primary rays sometimes 15 cm. long; scales lanceolate, thin, acute, light browr 

 bristles about 6, rigid, upwardly scabrous; style subulate, entire or minutel 

 2-toothed at the apex, 2-4 times longer than the achene, upwardly scabrou 

 1-2. 5 cm. long, much exserted beyond the scales when mature; achene obovate, fla 

 4 mm. long, dark brown, smooth. In. swamps, Del. to Fla., Ohio, Mo. and Te: 

 July-Sept. 



Rynchospora corniculiita rnacrostiichya (Torr.) Britton. Bristles about twice 

 long as the achene. Range of the type, but extending north to Mass. 



2. Rynchospora pallida M. A. Curtis. Pale Beaked-rush. (I. F. f. 64c 

 Rootstocks slender ; culms triangular, 0.3-0.6 m. tall. Leaves 1-2 mm. wid 

 nearly smooth, the lowest reduced to scales ; spikelets numerous, spindle-shape 

 4-6 mm. long, aggregated in a compound terminal head, or occasionally also in 

 cluster bom the upper axil; uppermost leaves subulate; scales pale greenish brow 

 lanceolate, acuminate; bristles minute and early deciduous, or wanting; style 

 cleft ; achene lenticular, oboyate-oblong, smooth, brown, shining, 1 mm. Ion 

 tipped by a short tubercle. In pine-barren bog-. X. J. to N. Car. Aug.-Sept. 



3. Rynchospora oligantha A. Gray, i i:\v-i lowered Beaked-rush. 

 F. f. 650.) Rootstocks short ; culms almost thread-like, leafy toward the ba 

 1.5-4 dm. tall. Leaves filiform ; spikelets 1-4, terminal, narrowly oblong, acu 

 6-8 mm. long, subtended by 1 or 2 filiform bracts; scales ovate, pale brown, acu 

 cuspidate ; bristles usually (>. densely plumose below the middle ; style 2-cle; 

 achene obovoid-oblong, obtuse, pale brown, dull, transversely wrinkled ; tuber 



