parts per culm, the terminal part irregularly corymbiform, dense, nearly erect, 

 2-6 cm. broad, of 100 to 200 spikelets or less commonly fewer; spikelets ovoid to 

 narrowly ovoid, 2.5-3 mm. long, dark-rich-brown, with 3 or 4 flowers and setting 

 2 or 3 fruits; bristles about 6, from half as long as to as long as the body or 

 rarely nearly equaling the tubercle, stiffly erect and mostly appressed to the body, 

 minutely antrorsely serrulate; achenial body obovate, 1-1.2 mm. long, 0.8-1.2 

 mm. broad, the 2 nearly flat or very slightly convex faces with strong transverse 

 wrinkles; tubercle deltoid, 0.2-0.5 mm. long. 



Rare in moist or wet sand, s.e. Tex. (Aransas Co.), summer; near the coast, 

 Fla. and Ga. to Tex.; Bah. I., Hisp. and Cuba. 



22. Rhynchospora perplexa Small. 



Tufted perennial; culms 5-11 dm. long, 1.5-2 mm. thick basally, wiry, erect 

 or very slightly flexuous in the floriferous region; leaf blades 1-2 mm. broad 

 basally, mostly strongly involute; inflorescence in 1 to 3 parts per culm, the 

 terminal part very irregularly cormbiform, 1-4 mm. broad, usually dense and with 

 upwards of 100 to 200 spikelets; spikelets ovoid, rich-dark-brown, 2.5-3 mm. 

 long; bristles about 6 or fewer, less than half as long as the body to which they are 

 appressed or reduced to virtual absence; achenial body obovate, 1-1.3 mm. long, 

 0.9-1.2 mm. broad, tawny, the 2 nearly flat or very slightly convex faces with 

 strong transverse wrinkles; tubercle deltoid, 0.2-0.3 mm. long. 



Rare in moist or wet sand in e. and s.e. Tex. (Aransas, Hardin, Tyler and 

 Waller cos.), late spring-summer; Coastal States, s.e. Va. to Tex.; Tenn.; Gr. Ant. 



Probably not specifically distinct from R. microcarpa. 



23. Rhynchospora caduca Ell. Fig. 249. 



Rhizomatous perennial; culms 7-13 dm. long. 2-4 mm. thick near the base, 

 ascending but quite flexuous in the upper part; leaves 4-7 mm. broad below the 

 middle, tapering in both directions; inflorescence of 3 to 5 parts per culm, the 

 terminal part obovoid, irregularly corymbiform, 2-4 cm. broad, with 60 to 125 

 spikelets, some of the primary branches commonly elongate, erect and 1-2 cm. 

 long; spikelets rich-dark-brown, ovoid, 4-4.5 mm. long, with 3 to 6 flowers and 

 setting 2 to 5 fruits; bristles about 6, surpassing the tubercle and somewhat stiffly 

 spreading away from the body basally, minutely antrorsely serrulate; achenial 

 body obovate, 1.4-1.7 mm. long, 1.2-1.6 mm. broad, the 2 faces with strong 

 transverse wrinkles and at least in the upper part pronouncedly convex; tubercle 

 deltoid, 0.6-0.8 mm. long. 



Frequent in moist or wet sand in Okla. (McCurtain Co.) and s.e. Tex. (Liberty 

 and Polk cos.), less frequent in e. Tex. (Bowie Co.) and very local in Burnet 

 and Llano cos. on the Edwards Plateau, summer; Coastal States, Va. to Tex.; 

 also Ark. and Okla. 



24. Rhynchospora globularis (Chapm.) Small. Fig. 253. 



Tufted perennial; culms (15-) 30-75 (-90) cm. long, 1-1.8 (-2.5) mm. thick 

 near the base, basally often shortly reclining, mostly erect, leafy with the old 

 sheaths basally becoming somewhat fibrous; blades 1.5-4 mm. broad; inflorescence 

 in 1 to 4 parts per culm, the terminal part usually strictly erect, of several 

 straight stiffly ascending unequal branches each topped by a corymbiform 

 glomerule 8-15 mm. broad (broader than high) and often with stiffly erect 

 setaceous protruding bracts; spikelets ovoid, 2.5-4 mm. long, cinnamon-brown, 

 with 1 to 4 flowers and setting 1 to 3 fruits; bristles about 6, shorter than the 

 body of the achene, minutely antrorsely serrulate; achenial body obovate, 1.2-1.6 

 mm. long, 1-1.5 mm. broad, castaneous, with 2 faces which are convex at least in 

 the upper part and have strong transverse wrinkles; tubercle deltoid, 0.3-0.6 mm. 



487 



