CTPERACEiE. 408 SCIRFUS. 



1. M. ovui.a'kis. 



Stem triangular, nearly naked, about a foot high ; ?ffl»fs shorter than the 

 stem, nearly smooth; umbel simple ; riiys short; heads 1 — 5, globose, middle 

 one sessile, tlie rest on the spreading rays ; inoolucre 4 — 5-leaved, unequal, 2 

 of them much longer than the lest. Bogs and low grounds. Aug. 



p. tenella (Torr.) ; sZem slender, acutely triangular ; 3 of the involucrate 

 leaves much longer than the umbel. 



2. M. rf.trofra'ctus. 



Slem triangular, naked, about 2 feet high ; lerives linear-lanceolate, half as 

 lonw as the stem ; vmbel simple ; rays long, unequal, (i — 8 ; involucre 3-leaved, 

 shorter than the rays: spikelets subulate, retrorsely imbricated into obovate 

 spikes. Wet grounds. Aug. 



3. DULI'CHIUM. 

 Spikes axillary, racemose; spikeleis linear-lanceolale, sub- 

 compressed ; glumes sheathing, closely imbricated in 2 rows; 

 stylo long, bifid, the persistent base crowning the compressed 

 achenium; ovary invested with setas. 



D. spatha'ceum. 



Slem round, leafy and somewhat 3-sided above, thick, sheathed below ; leaves 

 alternate, pointing 3 ways, 2 — 4 inches long, 3 lines wide; sheaths tubular, 

 shorter than the internodes ; spilccs axillary from within the sheaths and ter- 

 minal, each consisting of 8 — 10 linear-lanceolate, alternate spikelets in 2 

 rows; spikelets 5 — 7-flowered, nearly an inch in length; ^^M?Hes ^linear- 

 lanceolate. Aug. Per. 



Tribe 2. SCIRPE^.. 



Floicers perfect or monocUnous. Spikelets with the glumes imbricated all around. 



4. FUIRE'NA. 

 Glumes awned, imbricated on all sides into a spike; peta- 

 loid scales 3, cordate, awned, unguiculate, investing the 

 achenium. 



F. squARRo'sA. /3. pumila. Torr. 



Stem pubescent above, 3 — G inches high; leaves linear-lanceolate, flat, 

 striate, as long as the stem ; spikes 1,2 or 3, thick, subtended by 2 — 3 long, 

 involucrate, unequal leaves; glumes ovate-lanceolate, with short awns; 

 psta'oid scales ovate-lanceolate ;' achenium pedicellate, with retrorsely hispid 

 seta;. Wet, sandy places. Aug. 



5. SCIRPUS. 

 Spikelets ovoid, many-flowered, with glumes imbricated all 

 around ; ovary sometimes naked, but commonly invested with 

 selas or long hairs. 



i 1. Ovary invested with hypo^ynous setre. Style bifid, deciduous. Setfc straight, dis- 

 tinctly liispid. Spikelets sublerminal or lateral. Scikpus verus. 



1. S. TRi'QtiETER. jMx. Triangular Club-rash. S. Americanus. Pers. 



Stem nearly naked, 3-angled, corners acute and two of the sides concave, 

 about 3 feet high and ending in a sharp point ; leaves few and short, from the 

 top of tlie sheatli ; spikes hiUTd], 1 — .5, ovate, crowded and sessile, .it various 

 distances below the point ; glumes round-ovate mucronate ; bristles G. Ponds 

 and marshes, fresh and salt. July. 



