HEMJCARPHA. CLX. CYPERACE^. 573 



base ; spikelets 2 4, on short peduncles, nodding ; seta 40 60 to a flower, long, 

 white and cottony. Swamps, N. States and Brit. Am. July. 



6. E. VIRGINICUM. Virginian Cotton grass. 



St. nearly round, leafy, smooth, 2 3f high ; Ivs. flat, few, long, with 

 scabrous margins ; invol. 2 4-leaved, outer leaves much longer ; spikelets in a 

 sort of umbel, erect, nearly sessile ; glumes ovate, brown at the sides ; keel 

 green ; hairs 50 60, reddish-white, long and cottony. Wet grounds, U. S. 

 and Can. 



9. FIMBRISTYLIS. Vahl. 



lAi.f,mbria, a fringe, styltis, style ; from the ciliate style. 



Glumes imbricated on all sides ; bristles ; style compressed, 

 2-cleft, bulbous at base, deciduous, often ciliate on the margin. % 

 with the habit of Scirpus. 



1. F. BALDWINIANA. Torr. (Scirpus Baldwinianus. Schult. S. ferrugin- 

 eus. Darl.} St. 2 12' high, compressed, deeply striate, leafy at base ; 



umbel mostly simple, 3 4-rayed, central spikelets sessile; invol. subulate, 

 2-leaved, as long as the umbel ; spikelets ovoid, acute ; glumes ovate, brown ; 

 sty. bifid, ciliate; ach. white, longitudinally furrowed. Swamps and damp 

 places, Middle, Southern and Western States. July. 



2. F. SPADICEA. Vahl. (Scirpus spad. Linn. S. castaneus. Michx.} 



St. 1 2f high, hard and rigid, compressed, nearly naked; Ivs. 5 6' 

 high, filiform, channeled inside, semi-terete outside, lower ones rust-colored ; 

 umbel of few rays, rather exceeding the 2 3 subulate, involucre leaves; spikes 

 ovate-oblong, 3 6" long ; glumes broad-ovate, mucronate, finally of a dark, 

 shining, chestnut brown; sty. conspicuously fimbriate ; ach. whitish. Marshes, 

 N. J. to La. Aug. 



10. TRICHELOSTYLIS. Lestiboudois. 



Gr. rpi^TjXoj, three-fold, OTV\OS ] from the character. 



Glumes in 4 8 ranks, carinate ; bristles ; style 3-cleft, decidu- 

 ous below the bulb at the base ; achenium triangular. % Stems leafy 

 at the base. Spikes usually in terminal umbels. 



1. T. MUCRONULATUS. Torr. (Scirpus muc. Mickx. Fimbrisiylis autum 

 nalis. R. <$ S.) St. compressed, 2-edged, caespitose, leafy at base, 3 10' 



high ; Ivs. flat, linear, shorter than the stem ; umbel compound ; invol. 2-leaved ; 

 spikelets lanceolate, acute, somewhat 4-sided, 2 3 together; glumes brown, 

 mucronate; ach. white. Wet places, along rivers, &c., N. Eng. ! to Ga., W 

 to Mo. July. 



2. T. CAPILLARIS. Wood. (Scirpus. Linn. Isolepis. R. fy S 1 .) 



St. caespitose, nearly naked, 3-angled, capillary, 4 8' high; Ivs. subradd- 

 cal, setaceous, shorter than the stem ; spikelets ovoid, 2 4, pedunculate, innei 

 one sessile ; glumes oblong, ferruginous, margin pubescent ; ach. white. Ir 

 sandy fields, Mass, to Car., W. to Ky. and Ohio. Aug. 



11. HEMICARPHA. Nees. 



Gr. fipurvs, half, Kap<pa, straw or chaff? 



Glumes imbricated all around ; bristles ; stam. I ; style 2-cleft, 

 not bulbous at base, deciduous ; achenium compressed, oblong, sub- 

 terete. Q Spikes glomerate. 



H. SQ.UARROSA. Nees. (Isolepis subsquarrosa. ScKrad. Scirpus subsq. 



Muhl. S. minimus. PA.) Scape setaceous, compressed, sulcate, recurv- 

 ed, 2 3' high ; Ivs. setaceous, shorter than the scape ; spikes 2 3, terminal 

 (apparently lateral), subsessile, ovoid, nearly 2" long ; invol. of 2 bracts, one 

 appearing like a continuation of the scape, thrice longer than the other ; glumes 

 00, with a short, recurved or squarrose point, finally brown ; ach. minute, of a 

 dull, brownish-white. Sandy banks, N. Eng. ! to Penn. and Ky. 



