574 CLX. CYPERACEyE. RHYNCHOSPORA. 



12. PSYLOCARYA. Torr. 



Flowers . Glumes 00, imbricated all around, all fertile ; peri- 

 gynium ; stain. 2 ; filaments long, persistent ; style 2-cleft, dilated 

 or tuberculate at base ; achenium biconvex, crowned with the per- 

 sistent style. Stems leafy. Spikes lateral and terminal, cymose. 

 P. sciRpolDEs. Torr. ft 



St. slender, leafy, smooth, 3-sided, 5 9' high ; Ivs. linear, smooth, 3 5' 

 by I", cauline about 2 ; cymes terminal, and one from the sheath of each cau- 

 line leaf; spikes about 3" long, oblong-ovate, in small, loose clusters, 20 30- 

 flowered ; glumes chestnut-colored, thin, ovate, acute ; ach. tumid, dark brown, 

 crowned with the long style, which is much dilated at base. Borders of ponds, 

 Smithfield, R. I., Olney ! Mass., Greene. Rare. 



13. RHYNCHOSPORA. Vahl. 



Gr. pvv%os, a beak, Gxopa, seed; from the character. 



Flowers $ or $ $ 9 , few in each spikelet ; glumes loosely imbri- 

 cated, the lowest small and empty j perigynium of 6 12 bristles; 

 stam. 3 ; style bifid ; achenium lens-shaped or subglobose, crowned 

 with the distinct, bulbous base of the style. *4- Stem leafy, 3-sided. 

 Inflorescence, terminal and axillary. 



* Achenium smooth. 



1. R. ALBA. Vahl. (Schoenus albus. Linn.') White Bog-Rush. 



St. triangular above, very slender, leafy, smooth, 10 16' high ; Ivs. seta- 

 ceous, channeled; corymbose fascicles pedunculate, both terminal and from the 

 axils of the sheaths, with setaceous bracts ; spikelets lanceolate, acute at each 

 end, with crowded, lanceolate, white glumes. In wet, shady grounds ; com- 

 mon. July Sept. 



2. R. CAPILLACEA. Torr. (SchcEnus. Muhl.) 



St. 6 12' high, filiform, glabrous, triangular ; Ivs. setaceous, much shorter 

 than the stem ; spikelets 3 6, mostly terminal, oblong, each with a setaceous 

 bract ; glumes chestnut-colored, with scarious edges ; bristles 6, much longer 

 than the oblong, substipitate achenium ; tubercle about half the length of the 

 achenium. Swamps, N. Y., Sartwell, Penn., Muhl. 



3. R. FUSCA. Roem. & Schult. (Schoenus fuscus. Linn.) 



St. 3-angled, about 2f high ; Ivs. linear, carinate, smooth ; fascicles alter- 

 nate, pedunculate ; bracts setaceous, longer than the ovoid spikes ; glumes brown, 

 ovate ; ach. brown, rugose, with an acute, black tubercle as long as the hispid 

 bristles. Wet places, Mass, to N. J. Rare. 



4. R. GRACILENTA. A. Gr. 



St. 1 2f high, very slender or filiform, smooth; Ivs. linear-setaceous, 

 much shorter than the stem ; corymbs small, fasciculate, the lateral on slender 

 peduncles exserted from the sheaths; spikelets ovoid; glumes ovate, acute, dark 

 brown ; bristles 6, a third longer than the roundish-ovoid achenium ; tubercle 

 flat, dilated at base. Dry grounds, N. Y. to Car. 



5. R. GLOMERATA. Vahl. (Schcenus. Linn.) 



St. slender, smooth, leafy, a foot or more high ; Ivs. flat, carinate, rougn- 

 edged ; corymbed fascicles very remote, in pairs, axillary and terminal ; spikelets 

 lanceolate ; glumes keeled, mucronate, brown ; ach. obovoid or cuneiform, very 

 smooth, as long as the tubercle ; seta 6, rough, backwards. In bogs, Can. to 

 Flor. July, Aug. 



6. R. CEPHALANTHA. A. Gr. 



St. 2 3f high, triangular, stout ; Ivs. linear, very narrow, the lower and 

 radical nearly as long as the stem ; hds. roundish, axillary and terminal, soli- 

 tary or rarely two together ; spikelets lance-oblong ; glumes ovate-oblong, dark 

 brown ; bristles 6, twice longer than the achenium ; ach. roundish-ovoid, a little 

 compressed, very obtuse. N. J. pine barrens. 



