534 CTPERACEJE. (SEDGE FAMILY.) 



+- < Spikes 4-10, disposed in a simple spike or head, or (in No. 6) the lowest ones 

 compound 



6. C. sparganioides, Muhl. Spikes 6- 10, ovoid, the upper ones crowd- 

 ed, the lower scattered and often compound ; perigynia flattened, ovate, acute at 

 the base, narrowly margined, nerveless, spreading, with a short and rough 2-cleft 

 beak, twice as long as the thin ovate scale. Upper districts of Georgia, and 

 northward. Culms stout, 2 high. Leaves broadly linear, as long as the culm. 

 Common spike 2' -4' long. Perigynia yellowish. 



7. C. Muhlenbergii, Schkr. Spikes 5-8, ovoid, approximate, or crowd- 

 ed in dn oblong head ; perigynia round-ovate, plano-convex, strongly nerved, 

 with a short and broad rough-edged 2-cleft beak, barely longer than the ovate 

 short-pointed scale. Dry sterile soil, South Carolina, and northward. Culms 

 12'- 18' high, rigid, rough above, twice as long as the narrow leaves. Head or 

 spike 1' long. Bracts bristle-form, longer than the spikes. 



8. C. cephalophora, Muhl. Spikes 5-6, small, crowded in a compact 

 ovoid head ; perigynia broadly ovate, few-nerved, short and rough-beaked, as long 

 as the ovate long-pointed scale. Dry soil, Florida, and northward. Culms 

 9-'- 15' high, naked above, rough on the angles, tough and wiry. Leaves nar- 

 row. Head ' long. Bracts bristle-like. 



9. C. TOSea, Schk. Spikes 4-6, 8- 10-flowered, the two upper ones ap- 

 proximate, the others scattered , perigynia oblong, plano-convex, rough-beaked, 

 spreading at maturity, twice as long as the broadly ovate obtuse or short-mucronate 

 scale. (C. radiata, Dew., a form with more slender culms, and 3 - 4-flowered 

 spikes.) Upper districts, Georgia, and northward. Culms 1 high, smooth, 

 longer than the narrow leaves. Common spike 2' - 3' long. Bract of the lowest 

 spike commonly exceeding the culm. 



10. C. retroflexa, Muhl. Spikes 4 -5, crowded, or the lower ones dis- 

 tinct, ovoid, the lowest short-bracted ; perigynia ovate-lanceolate, smooth-beaked, 

 2-cleft, at length widely spreading or reflexed, barely longer than the ovate long- 

 pointed scale. Open woods, Florida, and northward. Culms slender, 1 high, 

 rough-angled above. Leaves narrow, shorter than the culm. Common spike 

 about 1' long. 



* '* * Spikes with the lower flowers sterile, the upper fertile. 



11. C. stellulata, Good. Spikes 3-5, obovoid, distinct, the uppermost 

 club-shaped at the base , perigynia ovate, rounded at the base, tapering into a 

 short and rough 2-cleft beak, finely nerved, spreading and finally recurved, 

 rather longer than the ovate pointed scale. (C. scirpoides, Schk.) Shady 

 river-swamps, Florida, and northward. Culms 6'- 12' high, weak. Leaves 

 narrow and tender. Spikes small. 



Var. sterilis. Sterile and fertile spikes on separate culms, or some of them 

 either sterile or fertile on the same culm, otherwise like the preceding, and grow- 

 ing in similar places. (C. sterilis, Willd.) 



Var. conferta. Culms taller (2 high) and stouter ; spikes larger and more 

 crowded; perigynia round-ovate, twice as long as the broadly ovate barely 

 pointed scale. Pine-barren swamps. 



