OoO CYPKHACK.i:. fsKIXilC FAMILY.) 



orbii'uhir, stron<^ly wrinklcil ; tuhercle c-OTiiprcsscd, very sliort, sessile, hut not 

 dccurrent on tlie oilgos of the nut. (Scirpus nitons, Vuhl ) — Shallow pine- 

 barren ponds, Florida to North Carolina. July. ® — Culms commonly root- 

 ing at the lower joints. 



P. sciRPOiDES, Torr., if within our limits, may be known by its nearly smooth 

 nut, and slender bcak-likc decurrent tubercle. 



18. DICHROMENA, Puchard. 



Spikes compressed, few-flowered, aggregated in a terminal head, and sur- 

 rounded by an involucre of several leaves, which arc commonly white at the 

 base. Scales imbricated in few rows, most of them bearing abortive flowers. 

 Stamens 3. Style 2-cleft. Nut lenticular, crowned with the broad and persist- 

 ent base of the style. Perianth none. Perennials. Culms jointless, leafy at 

 the base. itScalcs white, membranaceous. 



1. D. leucocephala, Michx. Culms (1°-1;}° hi;.-h) slender, 3-angled ; 

 leaves narrowly linear ; involucre of 4 - 7 narrow leaves ; nut orbicular, wrinkled ; 

 tubercle flat, broadly conical, sessile, but not decurrent. — Damp soil, Florida to 

 North Carolina. Aug. and Sept. — Involucre unchanged in drying. 



2. D. latifolia, Baldw. Culms stout (2° -.3° high), nearly terete; leaves 

 broadly linear, el()ii;,^ated ; leaves of the involucre 8-9, tapering from the broad 

 (3"- 4" wide) base to the slender summit, becoming reudish ; nut ronnd-obovate, 

 faintly wrinkled ; tubercle flat, conical, obtuse, the sides decurrent on the edges 

 of the nut. — Low pine barrens, Florida to North Carolina. IMay-July. — 

 Heads larger than those of the preceding. 



19. CLADIUM, Browne. 



Spikes ovate, 1 - 2-flowcred. Scales loosely imbricated, the lower ones empty. 

 Perianth none. Stamens 2. Style 2 - 3-cleft, the divisions often 2 - 3-cleft, de- 

 ciduous. Nut globose-ovate, the pericarp thickened and corky near the apc.\. 

 Tubercle none. — Culms tall. Spikes disposed in axillary and terminal cyme- 

 like panicles. * 



1. C. effusum, Torr. (Saw-CiUass.) Culms (4° - 8° lii.uh) nearly terete; 

 leaves linear, elongated, saw-edged ; panicles numerous, difluse , spikes ,'^mall, 

 3-4 in a cluster, deep brown; scales about 6, the uppermost bearing a perfect 

 flower, the next below staminiferous, the others empty ; nut ovale, pointed, 

 wrinkled. (Scha-nus cffusus, Sirartz.) — Fresh or brackish marshes along the 

 coast, Florida to North Carolina, and westward. July and Aug. 



20. SCLERIA, L. Nirr-Rrsu. 



Flowers moncecious. Sterile spike few -many-flowered. Scales loosely im- 

 bricated in 2 - 3 rows. Fertile flowers solitary, separate or at the base of tho 

 sterile spike. Stamens 1-3. Style 3-cleft. Nut globose or ovntc. stony or 

 bony.— Chiefly pen^nniuls, witli eree|)ing rootstocks, and triangular Italy culms. 

 Spikes clustered, lateral and terminal. 



