CYPEEACEAE. 55 



3. Rynchospora tenuis Link, Jahrb. 1: 76. 1820. 



Rootstocks short, slender; culms very slender, tufted, 1.5-4 dm. long, 

 glabrous and smooth, erect or reclining. Leaves 0.5-2 mm. wide, as long as 

 the culm or shorter; corymbs of spikelets- 1-3, filiform-stalked; spikelets 

 usually rather loosely clustered, about -4 mm. long, narrowly lanceolate, acute, 

 pale, bearing a single achene; scales acute, the lower ovate, the upper 

 lanceolate; bristles none; style deeply 2-cleft; achene obovate or nearly orbi- 

 cular, sessile, transversely rugose, about 1 mm. broad; tubercle acute, one- 

 fourth to one-half as long as the achene and decurrent on its margins. 



Moist ground. Andros, New Providence : Cuba ; Dominica to Grenada ; trop- 

 ical continental America. Slender Beaked-rush. 



4. Rynchospora divergens Chapm. ; M. A. Curtis, Am. Journ. Sci. II. 7: 409. 



1849. 



Perennial; culms nearly filiform, densely tufted, 1-4 dm. high. Leaves 

 similar to the culms, usually somewhat shorter; spikelets loosely corymbose, 

 ellipsoid, acute, about 3 mm. long ; scales ovate to elliptic ; bristles none ; style 

 2-cleft, the branches about as long as the undivided part ; achene orbicular- 

 obovate, 0.5-0.8 mm. long, pale, reticulated, contracted at the base, the short 

 tubercle depressed. 



Moist soil, Great Bahama. Andros. New Providence : southeastern United 

 States ; Cuba. Low Beaked-rush. 



>c 5. Rynchospora perplexa Britton; Small, Fl. SE. U. S. 197. 1903. 



Perennial by rootstocks; culms slender, usually clustered, 3-12 dm. high. 

 Leaves flat, grass-like, elongated, smooth, 1.5-3 mm. wide; corymbs usually 

 several, rather loose, slender stalked; spikelets numerous, ovoid, about 2 mm. 

 long; scales brown, obtuse or acuti^h ; bristles 6, upwardly barbed, shorter 

 than the achene; style 2-eleft at the summit; achene biconvex, transversely 

 wrinkled, about 1 mm. long, the depressed tubercle broader than high. 



Wet grounds. Great Bahama, Abaco. Andros. New Providence, Eleuthera, Cat 

 Island : southeastern United States. Short-bristled Beaked-rush. 



6. Rynchospora microcarpa Baldw. ; A. Gray, Ann. Lye. X. Y. 3: 202. 1836. 



Perennial by rootstocks; culms rather slender, clustered, 11 dm. high or 

 less. Leaves flat or slightly channeled, 1-5 mm. wide; corymbs 3-6, slender- 

 stalked, with few or many ovoid spikelets about 2.5 mm. long; scales brown; 

 bristles 5 or 6, upwardly barbed, about as long as the achene or a little 

 longer; style 2-cleft at the summit; achene lenticular, transversely wrinkled, 

 scarcely 1 mm. long, the depressed tubercle blunt. 



Wet grounds, Andros, New Providence, Crooked Island : southeastern United 

 States. Small-fruited Beaked-rush. 



7. Rynchospora bahamensis Britton, Torreya 13: 217. 1913. 



Densely tufted; rootstocks short. Culms nearly filiform, roughish, spread- 

 ing or reclining, 2-3.5 dm. long; leaves setaceous-flattened, less than 1 mm. 

 wide, roughish-margined, the basal ones about one-fourth as long as the culm, 

 the upper 3-5 cm. long; spikelets oblong, 1.5-2 mm. long in 2-4 distant 

 slender-peduncled clusters, each with a single achene; scales dark brown, 

 ovate-oblong, mucronulate; achene elliptic-obovate, faintly transversely 

 wrinkled, 1.5 mm. long; tubercle flattened, conic, one-third to one-half as long 

 as the achene; bristles upwardly barbed, as long as the achene. 



Coppices and borders of swamps, New Providence, Andros : Cuba ; Forto 

 Rico. Bahama Beaked-rush. 



