ORDER 154. CYPERACE^E. 367 



dark-brown, in 1 or 2 small fascicles ; ach. half the length of the sehe which eqnal 

 the pointed serrulate tubercle. Maine to N. J., and W. Kare. Europe. 

 SIR. gracilleiita Gr. Tufts 1 2f; culm and leaves threadform, curved ; spikes 

 1", brown, in 23 fascicles; ach. oval, as long as its awl-shaped, serrulate tubercle, 

 shorter than the 6 setae. Low grounds, N. Y. to Fla. (R. filifolia Torr.) 



15. CERATOSCHCENUS, Nees. Spikelets 2-5-flwd., one flower $ 

 the rest $ . Glumes loosely imbricated, somewhat in 2 rows, lower ones 

 empty. Perianth of 5 or 6 rigid, hispid, or scabrous setae. Stamen? 3. 

 Style simple, very long, persistent as a beak on the smooth, compressed 

 achenium. y Stems leafy, 3-angled, 2 4f. Cymes compound, brown. 



1 C. longirostrls (Ell.) 3 5f; leave? flat, 46"; spikes in loose fascicles, 9"; 



ach. 2". beak 7", setae 5" ; cymes diffuse, terminal and axillary. Perm., W. and S. 



2 C. macrostachya Torr. Leaves 2 4" wide; spikes 1", in dense fascicles; ach. 



and beak 8", setrc 2 3", culm 2 3f. Hardly distinct. Mass., and South. 



3 C. capitatus* Chapm. Spikes densely clustered in a few heads; beak only 2", 



ach. 1", setje 2", culm teretish, 2 3f, leaves 24" wide. W. Fla. 



16. CLADIUM, Browne. Flowers (55?. Glumes imbricated some- 

 what in 3 rows, lower ones empty. Setae 0. Stamens 2. Style 2-3-cleft, 

 deciduous. Achenium subglobous, the pericarp hard, thickened and corky 

 above, it Stem leafy. Cymes terminal and axillary, brown. 



1 C. mariscoidcs (Muhl.) Bog Rush. Culm terete, rigid, 20 30' ; leaves narrowly 



linear, much shorter than culm ; spikes 3", in pedunculate or sessile heads, forming 

 small cymes ; ach. ovoid, scarcely beaked. Hogs, N. Eng., and West. 



2 C. efl'iisum (Swtz.) . Saiv Grass. Culm obtusely 3-angled, (i lOf, leaves 3 10ft 



sharply serrate-barbed on the edges ; cymes diffuse, decompound, forming a largo 

 panicle. A coarse, rank Sedge in ponds, N. Car. to La. 



17. SCL.ERIA, L. NUT SEDGE. Flowers 8 , staminate spikes inter- 

 mixed, fertile spikelets 1-flowered, glumes fasciculate. Perianth cup-shaped 

 or 0. Achenium globous, ovoid or triangular, with a thick, bony pericarp. 

 Style 3-cleft, deciduous. U Culms 3-angled, leafy. Spikes in fascicles. 

 Nuts white. In bogs. Summer. 



SCI,ERIA. Achenium ovoid or globous, base invested with a short, perigynium. . .(*) 

 " Achenium smooth, ovoid. Perianth annular, subentire. Stamens 3.. Nos. 1,2 



" Achenium rugous-warty, globular. Perianth 6- or 3-lobed Nos. 3, 4 



* Achenium reticulated or hispid-rugous, globular. Perianth 3-lobed Nos. 5, 6 



llYPOPORUM. Achenium ovoid-triangular, base fluted. Perigynium none... (a) 

 a Fascicles 4 to 7, interruptedly spiked. Achenium smooth or rugous.. Nos. 7, 8 

 a Fascicles single, terminal. Achenium ribbed or smooth Nos. 9, 10 



1 S. triglomerata MX. Whip Grass. Culm erect, rough, 3 4f; leaves broad- 



linear, rough-edged ; fascicles few, composed of triple clusters of green-brown (y e ) 

 spikes ; ach. white and polished, more than 1" in diameter. Common. 



2 S. leptoculmis W. Culm very slender, 2f, nearly naked ; Ivs. smooth, narrowly 



linear ; compound spikes loose, the lateral on a long filiform peduncle ; spikes 34"; 

 ach. pol shed, ovoid, minutely corrugated. S. (S. oligantha Ell.?) 



3 S. t-iliata MX. Culm scabrous above, 2f; leaves 2, pubescent, bracts ciliato- 



f'ringcd ; ach. beset with unequal warts, disk 3-lobed. Pine barrens, S. 

 i S. panciflora Muhl. Smoothish or hairy ; leaves and bracts exceeding the culm; 



