528 CYPERACE^. (sedge family.) 



late; nut obovatc from a stalk-liko base, lenticular; tubercle subulate, as long as 

 the nut, with its dilated base equalling it in width ; bristles G, stout, nearly as long 

 as tlio nut and tubercle. — Var. paniculata. (R. paniculata, Graij.) Culms 

 stout (3° -4° high) ; leaves flat (2" -3" wide) ; corymbs compound, paniculate, 

 with the very numerous spikes clustered at the summit of tlie branches. — Bogs 

 and springy places, Florida to North Carolina, and westward. July - Sept. 



27. E. cephalantha, Gray. Culms {2° - 3° high) nearly terete ; leaves nar- 

 rowly linear; corymbs 4-8, mostly by pairs, globose, compact; spikes numer- 

 ous, lanceolate-oblong, dark brown ; nut broadly obovate from a stalk-like base, 

 compressed, almost truncate at the apex, and much wider than the base of the 

 subulate tubercle ; bristles 6, as long as the nut and tubercle. — Bogs and shady 

 swamps, Florida, and northward. July and Aug. 



§ 3. HALOSCHGENXJS. Perianth none. 



28. R. pusilla, n. sp. Culms (6' -12' high) and leaves bristle-forra ; corymbs 

 2-3, distant, erect-spreading, the upper one compound; spikes minute, ovate, 

 mostly scattered on the branches, 3-flowered ; scales ovate, brown ; nut white, 

 oblong-obovate, compressed-lenticular, contracted at the base, transversely 

 wrinkled ; tubercle depressed-conical, free at the base. — Margins of pine-barren 

 ponds, Middle and West Florida. June. 



29. R. divergens, u sp. Culms (6'- 12'.high) and leaves filiform or bristle- 

 form; corymbs 2-3, distant, spreading; spikes small, scattered, pcdicelled, 3- 

 flowered; scales brown, ovate ; nut obovate, biconvex, minutely pitted ; tubercle 

 depressed, sessile, minutely pointed in the centre. — Low pine barrens, Florida 

 to South Carolina. June. 



30. R. Chapmanii, M. A. Curtis. Culms (12'- 20' high) densely tufted, 

 erect, setaceous or filiform, like the short and flat leaves ; corymb solitary, terminal, 

 capitate; spikes whitish, lanceolate, densely clustered, 1-flowered; scales 5, the 

 uppermost fertile ; nut oval, lenticular, smooth and shining ; tubercle short, ses- 

 sile, broadly conical ; stamens 1-2. — Flat pine barrens, Florida to South Caro- 

 lina. July and Aug. 



15. CERATOSCHCENITS, Nees. Hokned-Rush. 



Spikes few-flowered. Scales loosely imbricated, the lower ones empty, the 

 upper with staminate or abortive flowers. Perianth of 4-6 bristles, which are 

 dilated and connate at the base. Stamens 3. Style elongated, entire or slightly 

 2-cleft at the apex. Nut compressed, crowned with the persistent and hispid 

 lower half of the style. — Perennials. Culms jointed, leafy. Spikes scattered 

 in an open corymb, or clustered in a globose head. 



1. C. corniculatus, Nees. Culms stout (3° -4° high), 3-angIed; leaves 

 flat, scabrous on the edges (6"-10" wide) ; corymbs 3 -5, erect, compound ; spikes 

 brown, ovate-lanceolate ; style very long, the lower and persistent portion up- 

 wardly scabrous ; nut narrowly obovate, smooth, the sides concave and minutely 

 dotted ; bristles 5-6, rigid, smoothish, half as long as the nut ; tubercle subulate, 

 3-4 times the length of the nut. (Rhynchospora longirostris, Ell.) — Ponds 



