524 CYPERACE^. (sedge FAMILY.) 



of the style (tuberclcd). Perennials, with jointed and leafy culms. Spikes 

 small, disposed in axillary and terminal corymbs or clusters. 



§ 1. KKIOCH^TE. Bristles of the perianth &, plumose. 



1. R. plumosa, Ell. Culms (6' -12' high) and leaves filiform; spikes 

 few, in about three small clusters at the summit of the culm ; nut nearly globu- 

 lar, strongly wrinkled, pointed with the short ovate smooth tubercle ; bristles 

 rather longer than the nut, plumose throughout or nearly to the summit. — Low 

 pine barrens, Florida to North Carolina. June and July. 



Var. intermedia. Culms taller (\°-2° high); leaves narrowly linear; 

 clusters 4-6, forming an interrapted spike at the summit of the culm ; nut obo- 

 vatc, pointed with the conical-beaked pubescent tubercle ; bristles plumose only 

 at the base, or below the middle. — Sandy pine barrens, often dry places, Florida. 



2. R. semiplumosa, Gray. Culms erect, rigid (l°-2° high); leaves 

 narrowly linear ; spikes oblong-ovate, dark brown, crowded in a terminal head, 

 or rarely in a remote axillary one ; nut globose-obovate, faintly wrinkled, pointed 

 with the short broadly conical smooth tubercle ; bristles exceeding the tubercle, 

 plumose below the middle. — Dry sandy ridges, near the coast, West Florida. 

 July and Aug. — The leaves, like those of the preceding species, have a joint- 

 like contraction near the middle. 



3. R, oligantha, Gray. Culms (6'- 12' high) and smooth leaves bristle- 

 like, reclining ; corymb terminal, of 3 - 6 large (4" long) ovate-lanceolate whitish 

 stalked spikes; nut oval, lenticular, faintly wrinkled ; tubercle dilated at the base, 

 conical, flat; bristles longer or shorter than the nut, plumose below the middle. 



— Low open pine barrens, Florida to North Carolina. June and July. 



If 2. RHYNCHOSPORA Proper. Bristles of the perianth 3 - 20, smooth, 



scabrous, or hispid. 



* Nut transversely wrinkled or uneven : bristles denticulate or hispid upward. 



•*- Bristles shorter than the nut. 



4. R. rariflora, Ell. Culms and leaves bristle-form; corymbs 2-3, re- 

 mote, spreading; spikes few and scattered, ovate; nut broadly obovate, bicon- 

 vex, strongly wrinkled, twice as long as the 6 fragile bristles ; tubercle flat, 

 broadl}' conical, J as long as the nut. — Low grassy pine barrens, Florida to 

 North Carolina. June and July. — Culms 1°-1^° long, commonly reclining. 

 Spikes pcdiccllcd. 



5. R. Torreyana, Gray. Culms erect, slender, nearly terete ; leaves nar- 

 rowly linear or bristle-form ; corymbs 1-3, remote, erect ; nut obovate, flat, aliout 

 twice as long as tlie 6 bristles ; tubercle c-omprcssed-conical, dilatid at tlie base, 

 ) the length of the nut. — Wet ground, South Carolina, and nortiiwnrd. July. 



— Culm l°-3°liigh. Corymbs many-flowered and somewliat spreading, or 

 fow-flowered and capitate. 



6. R. cymosa, Nutt. Culms (2° - 3° high) 3-anglod ; leaves nanowly 

 linear; corymbs mostly 3, distant, open or contracted ; spikes ovate, clustered, 

 light brown ; scales murronate ; nut broadly olmvate, biconvex, faintly wririkled, 

 ivricc as long as the 3-6 bristles; luberclu broadly conical, cumj>rejjsed, \aa 



