674 CLX. CYPERACEiE. Rhynchospora. 



12. PSYLOCARYA. Torr. 



Flowers 5 . Glumes 00, imbricated all around, all fertile ; peri- 

 gynium ; stam. 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. sciRPoiDEs. Torr. 



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

 by 1", cauline about 2 ; cijmcs 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., Olncy ! Mass., Greene. Rare. 



13. RHYNCHOSPORA. Vahl. 

 Gr. pvv^os, a beak, anopa, seed; from the character. 



Flowers 5 or c? $ 9, few in each-spikelet : glumes loosely imbri- 

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

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

 with the distinct, bulbous base of the style. — % Stem leafy, 3-sided. 

 Lijlorescence terminal and axillary. 



* Achenium smooth. 



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



St. triangular above, very slender, leaf}^ 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. (Schoenus. MuM.) 



St. 6 — 12' high, filiform, glabrous, triangular ; lis. 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., Sartu-ell, Penn., Muhl. 



3. R. FuscA. Rcem. & Schult. (Schcpnus 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, rugo.se, with an acute, black tubercle as long as the hispid 

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



4. R. GRACILF.NTA. 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 roundi.sh-ovoid achenium; tid)ercle 

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



5. R. GLOMERATA. Valil. (Schoeuus. Linn.) 



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

 edged; coryrnbed 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 ; setcc G, rough, backwards. — In bogs, Can. to 

 Flor. July, Aug. 



6. R. CEPHAI.ANTHA. 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 (J, twice longer than the achenium ; ach. roundish-ovoid, a little 

 compressed, very obtu.se. — N. J. pine barrens. 



