548 CYPERACEJE. (SEDGE FAMILY.) 



9. S. atrovirens, Muhl. Culm 2 -4 high, obtuse-angled ; leaves pale, 

 6"- 10" wide; umbel erect ; clusters of spikes closely packed in large green- 

 ish brown heads ; scales oblong, pointed ; bristles rather longer than the white 

 compressed obovate pointed nut, naked below the middle. Marshes and 

 wet banks in the upper districts. July. 



10. S, divaricatUS, Ell. Culm round-angled, many-jointed ; leaves flat, 

 broadly linear; umbel large, widely spreading or drooping, decompound, 

 longer than the 3-leaved involucre ; spikes all single, oblong-linear, scattered : 

 scales ovate, obtuse, 3-nerved, brown on the sides ; bristles hair-like, rather 

 roughened than hispid, crisped at the summit, longer than the obovate pointed 

 equal-sided, acute-angled nut. Muddy banks of the Chipola Kiver, and of 

 Flat Creek, near Aspalaga, Florida to South Carolina ; not common. Au- 

 gust. Culm 2 -4 high, often proliferous at the joints. Umbel 6' -12' 

 long. Spikes 2" - 3" long. 



11. S. (?) SUbmersus, Sauvalle. Culm floating, terete, sheathed ; um- 

 bel large, decompound, leafy, the leaves short, capillary, clustered like the 1- 

 flowered pedicelled spikes ; scales two, linear, the lower empty ; style 2-cleft; 

 nut obovate, lenticular, puucticulate, pointed by the persistent base of the 

 style, shorter than the 6-10 capillary bristles. (Websteria limnophila, S. H. 



Wright.) Lakes and ponds, Volusia County, Florida (G. \V. Webster). 

 Culm 1 - 3 long. Leaves 1 ' - 3' long. Spikes 4" - 6" long. 



* * Bristles 6, capillary, smooth, crisped and entangled. (Trichophorum.) 



12. S. Eriophorum, Michx. Culm nearly terete, with the joints re- 

 mote ; leaves linear, elongated, keeled ; umbel terminal, decompound, spread- 

 ing or recurved, shorter than the 3-5-leaved involucre; spikes single or 

 clustered, ovate ; scales thin, lanceolate, obtuse ; bristles many times longer 

 than the oblong compressed-3-angled beak-pointed nut, at length exserted, and 

 covering the spike with woolly down. Swamps and low grounds, Florida, 

 and northward. July - Sept. Culm 2- 4 high. 



13. S. lineatus, Michx. Culm 3-angled; leaves flat, linear-lanceolate; 

 umbels lateral and terminal, longer than the 1 - 3-leaved involucre ; spikes all 

 single, cylindrical ; scales rigid, keeled, mucronate ; bristles barely exserted ; 

 nut as in the preceding. Swamps, Georgia, and northward. June -August. 



- Culm 2 - 3 high. Spikelets 3" - 4" long. 



3. Culms jointless : leaves radical : spikes capitate : involucre several-leaved. 



14. S. Cubensis, Poepp. & Kunth. Culm acutely 3-angular, leafy at 

 base (8'- 12' high), shorter than the leaves and the involucre; spikes obo- 

 vate, compressed, 12-flowered, closely packed in a terminal globular head ; 

 scales rigid, oblong-obovate, tapering into a stout spreading point, 13-nerved; 

 stamens 3 ; style deeply 2-parted ; nut ovate-lanceolate, acuminate, concavo- 

 convex ; bristles none. Marshes, New Orleans (Dr. Hale), Mobile (Mokr). 



9. ERIOPHORUM, L. COTTON-GRASS. 



Spikes many-flowered. Scales imbricated in many rows. Perianth com- 

 posed of numerous (rarely 6) smooth and flat hairs, much longer than the 



