CYPERACEAE. 187 



2. Cladium effusum (Sw.) Torr. SAW-GRASS. Culm stout, 1.5-3 m. high, 

 obtusely 3-angled. Leaves verv long, glabrous, 6-2O mm. wide, the margins 

 spinulose-serrulate; umt>els several or numerous, decompound, forming a large 

 panicle; spikelets mostly 2-5 together at the ends of the raylets, narrowly ovoid, 

 acute, 4-5 mm. long; uppermost scale subtending a perfect flower; stamens 2; 

 achene ovoid, abruptly sharp-pointed, wrinkled, narrowed to the base, 2 mm. long. 

 In fresh water, southern Vu. to Fla. and Tex. Also in the W. I. Aug.-Sept. 



16. SCLERIA Berg. 



Leafy sedges, mostly perennial, the spikelets small, clustered in terminal, or 

 terminal and axillary fascicles, or sometimes interruptedly spicate. Flowers 

 monoecious. Fertile spikelets I -flowered. Staminate spikelets many-flowered. 

 Scales imbricated, the 1-3 lower and sometimes also the upper ones of the fertile 

 spikelets empty. Perianth none. Style 3 -cleft, slender or sometimes swollen at 

 the base, deciduous. Ovary supported on a disk (hypogynium), or this wanting. 

 Stamens 1-3. Achene globose or ovoid, obtuse, crustaceous or bony, white in our 

 species. [Greek, in allusion to the hard fruit.] About 100 species, natives of 

 tropical and temperate regions. Besides the following, some 4 others occur in the 

 southern U. S. 



Spikelets in terminal, or terminal and lateral clusters; achene supported on a hypo- 

 gynium. 



Achene smooth. 



Hypogynium supporting 8 or 9 small tubercles under the achene. 



i. S. oligantha. 



Hypogynium covered with a rough white crust. 2. S. triglomerata. 



Achene reticulated or irregularly rugose. 



Culms erect or ascending ; achene reticulated ; leaves 2-3 mm. wide. 



3. S. reticularis. 

 Culms spreading ; achene irregularly rugose ; leaves 4-8 mm. wide. 



4. S. Torreyana. 

 Achene papillose. 5. S. pauciflora. 



Spikelets interruptedly glomerate-spicate ; no hypogynium. 6. S. verticillata. 



1. Scleria oligantha Michx. FEW-FLOWERED NUT-RUSH. (I. F. f. 662.) 

 Rootstocks thick, hard, clustered. Culms slender, erect, sharply 3-angled, nearly 

 smooth, 0.4-0.6 m. tall. Leaves smooth or slightly rough at the apex, 4-6 mm. 

 wide, the lower short, acute, the upper elongated; clusters terminal, usually also 

 I or 2 axillary and filiform-stalked; bracts slightly ciliate or glabrous; achene 

 ovoid, obtuse but sometimes pointed, bright white, smooth, shining; hypogynium 

 a narrow obtusely triangular border supporting 8 or 9 small tubercles under the 

 achene. In moist soil, Va. to Fla. and Tex., near the coast. June- Aug. 



2. Scleria triglomerata Michx. TALL NUT-RUSH. (I. F. f. 663.) Root- 

 stocks hard, clustered; culms 3-angled, 0.4-0.9 m. tall. Leaves flat, glabrous or 

 nearly so, 3-5 mm. wide, the upper tapering to a long tip, rarely exceeding the 

 culm; flower-clusters terminal, and usually also I or 2 smaller ones from the axils; 

 achene ovoid or ovoid-globose, obtuse, bony, obscurely 3-angled, smooth, bright 

 white, shining, about 2 mm. high, supported on a low obtusely triangular, papil- 

 lose-crustaceous hypogynium. In meadows and thickets, Vt. to Wis., Fla. and 

 Tex. July-Sept. 



Scleria triglomerata minor Britton. Culms very slender, 0.2-0.3 m. long; flower- 

 clusters smaller; achene ovoid, subacute, one-half as large as that of the type. S. N. J. 



3. Scleria reticularis Michx. RETICULATED NUT-RUSH. (I. F. f. 664.) 

 Rootstocks small; culms slender, erect, 3-angled, 0.3-0.6 m. tall. Leaves nar- 

 rowly linear, glabrous or nearly so, 23 mm. wide, not overtopping the culm; 

 spikelets in a terminal cluster and 1-3 remote axillary rather loose ones; bracts 

 glabrous; achene globose, crustaceous, dull white when mature, reticulated, i mm. 

 in diameter, glabrous; hypogynium 3-lobed, its lobes appressed to the base of the 

 achene. In moist meadows, E. Mass, to Fla., west to Mo. Also in Cuba. July- 

 Sept. 



