CYPERACEAE 197 



elliptic, fully 1.5 mm. long, strongly transversely wrinkled, about twice as long as the 

 bristles ; tubercle low-conic. 



In grassy pine lands, North Carolina to Florida and Texas. Spring to fall. 



31. Rynchospora Torreyana A. Gray. Stems terete or obscurely 3-angled, smooth, 

 slender, 4-9 dm. tall : leaf-blades involute, the lower 3-4 mm. wide at the base, elongated, 

 the upper bristle-like, distant : spikelets ovoid, 3 mm. long, peduncled, numerous in 1-4 

 loose distant clusters : scales brown, ovate, mucronate : perianth-bristles 6, upwardly barbed : 

 achenes flat, oblong-obovate, transversely wrinkled ; tubercle flat, conic, J-J- as long as the 

 achene and continuous with it. 



In wet pine lands, New Jersey to South Carolina. Summer. 



32. Rynchospora Earlei Britton. Perennial, light green. Stems 3-8 dm. tall, 

 smooth : leaves mainly at the base of the stem ; blades narrowly linear, 1.5-3 mm. broad, 

 smooth : spikelets ovoid, 3.5-4 mm. long, acute, 2-6 in several cymose clusters on rela- 

 tively stout peduncles : scales red, acute or apiculate : perianth-bristles 6, shorter than the 

 achene : achenes strongly biconvex, broadly obovoid, 2 mm. long, transversely wrinkled, 

 reddish brown, constricted under the much depressed or nearly flat tubercle. 



In pine woods, Marshall ville, Georgia. Summer. 



33. Rynchospora perp!6xa Britton. Perennial, deep green. Stems 'slender, 5-11 

 dm. tall, often tufted : leaves mostly at the base of the stem ; blades narrowly linear, flat, 

 1-2. 5 mm. wide, usually much elongated, smooth : spikelets ovoid or orbicular-ovoid , about 

 2 mm. long, in a terminal and 1 or several axillary lax or rarely slightly congested corymbs 

 on very slender peduncles : scales brown, blunt or merely acute : perianth-bristles 6, 

 shorter than the achene : achenes biconvex, not constricted under the tubercle, about 1 mm. 

 long ; tubercle depressed, wider than high. 



In swamps and hammocks, North Carolina to Florida. Summer. 



34. Rynchospora cymosa Ell. Light green. Stems tufted, 3-angled, smooth, 3-8 dm. 

 tall : leaf-blades flat, narrowly linear, grass-like, 3-4 mm. wide or the basal ones broader : 

 bracts setaceous : spikelets ovoid-oblong, acute, 3 mm. long, sessile or nearly so, capitate 

 in 2's-7's on the ultimate branches of the axillary and terminal clusters : scales dark 

 brown, broadly ovate : perianth-bristles 6, upwardly barbed, shorter than the achene : 

 achenes broadly obovoid or oblong-obovoid , lenticular, 1.5 mm. long, transversely wrinkled ; 

 tubercle conic,- about as high as wide, J--J- as long as the achene. 



In moist soil, New Jersey to Kentucky, Missouri, Florida and Texas. Also in Cuba. Summer. A 

 variety with stems 1.5-3.5 dm. tall, corymbs of few ovoid-globose dark brown spikelets and more deeply 

 wrinkled achenes 1 mm. long, is R. ci/mosa globuldris Chapm.; it ranges from Florida to Louisiana. 



35. Rynchospora compr6ssa Carey. Perennial, pale green. Stems tufted, 6-1 2 dm. 

 tall, 3-angled : leaves several at the base of the stem ; blades rather rigid, 3-5 mm. broad, 

 smooth or nearly so : spikelets ovoid, 2-2.5 mm. long, numerous, in 3-5 peduncled 

 corymbs : perianth-bristles 6, shorter than the achene : achenes lenticular, flat, 2 mm. 

 long, coarsely transversely wrinkled, rhombie-obovoid, topped by a low conic tubercle with 

 a collar-like base, about twice as long as the bristles, contracted under the tubercle. 



About pine-land ponds, Florida and Alabama. Spring to fall. 



36. Rynchospora patula A. Gray. Perennial, bright green. Stems somewhat 

 tufted, 6-12 dm. tall, smooth, quite slender : leaves mainly on the lower part of the stem ; 

 blades narrowly linear, 2-6 mm. wide, smooth : spikelets ovoid, 3-3.5 mm. long, 1-3- 

 flowered, acute, many in terminal and axillary slender-peduncled compound corymbs : 

 scales brown, deciduous : perianth-bristles not longer than the achene and tubercle : achenes 

 lenticular, obovoid or orbicular-obovoid, barely 1.5 mm. long, transversely wrinkled ; tu- 

 bercle setose, surpassing the perianth-bristles. 



In sandy pine woods and swamps, North Carolina to Florida. Spring to fall. 



37. Rynchospora caduca Ell. Perennial, bright green. Stems often loosely tufted, 

 8-15 dm. tall, sharply 3-angled : leaves elongated ; blades 4-10 mm. wide, attenuate, 

 rough-margined : spikelets ovoid, about 4 mm. long, numerous in 4-6 compound corymbs : 

 perianth-bristles 6, longer than the achene and tubercle : achenes lenticular, orbicular- 

 obovoid, about 1.5 mm. long, finely transversely wrinkled, surpassed by the slender bris- 

 tles ; tubercle setose, conic. 



In swamps and on shaded banks, North Carolina to Arkansas, Florida and Texas. Spring to fall. 



38. Rynchospora mixta Britton. Perennial, pale or light green. Stems loosely 

 tufted, 3-angled : leaves mostly at the base of the stem ; blades 3-7 mm. wide, slightly 

 rough on the margins: spikelets 1-3-flowered, lanceolate in outline, 3.5-4 mm. long, 

 acute, in slender-peduncled lax corymbs : scales few, erect : perianth-bristles 6, longer than 

 the achene and tubercle : achenes lenticular, narrowly obovoid, less than 1.5 mm. long, 

 transversely wrinkled, about \ as long as the slender bristles ; tubercle depressed -conic, setose. 



In river swamps and low pine lands, Georgia and Florida. Spring to fall. 



