CYPERACEAE. 27 



6. C. Haspan L. Perennial, 3-10 dm. tall: leaves reduced to membranous 

 acuminate s^heaths: umbel simple or compound, the longer rays 2-5 cm. long: 

 spikelets few, capitate, linear, acute, many-flowered, G-12 mm. long, about 1 

 mm. wide : scales oblong or oblong-lanceolate, reddish-brown, acute, mucronu- 

 late: rachis winged: acheue broadly obovoid, 0.5-0.7 mm. long, obtuse, nearly 

 white, much shorter than the scale. — Everglades. — {Cuha, Ant.) 



7. C. rotundus L. Perennial, 1-5 dm. tall: leaf -blades 3-6 mm. wide: 

 umbel 3-S-rayed, the longer rays 5-11 cm. long: spikelets linear, clustered, 

 few in each cluster, acute, 8-20 mm. long, 2-3 mm. wide: scales purple-brown 

 or with green margins and center, ovate, acute, appressed: achene linear-oblong, 

 about 1 mm. long, about A as long as the scale. — Pinelands and hammocks. 

 {Ber., Bah., Cuba, Ant.) — Nut-gr.\s&, 



8. C. speciosus A''ahl. Annual, 1-4 dm. tall: leaf -blades rough-margined, 3-5 

 mm. wide, the niidvein prominent: umbel 3-7-rayed, the primary rays 2-15 cm. 

 long: spikes dull-brown: spikelets subterete, very narrowly linear, 8-25 mm. 

 long, less than 2 mm. thick, 10-30-flowered: scales dull-brown, thin, not 

 tightly appressed, ovate, obtuse: rachis-wings broad, clasping the achene, 

 persistent: achene obovoid, barely 1.5 mm. long, pale, 3-angled, about i as 

 long as the scale. — Everglades. — {Cuba, Ant.) 



9. C. Martindalei Britton. Perennial, 2-7 dm. tall: leaves overtopped by the 

 scape; blades filiform by the revolute margins, smooth: umbel capitate, or 

 with 1-3 slender rays: spikes globular, 1-2 cm. in diameter: spikelets linear or 

 linear-subulate, 6—10 mm. long, yellowish-green, densely crowded: scales 

 broadly oblong, 2-2.5 mm. long, prominently ribbed: achenes oblong, 2 mm. 

 long or nearly so, brown, dull. — Pinelands. — F. K. 



10. C. retrorsus Chapm. Perennial, 4-7 dm. tall : leaves overtopped by the 

 scape; blades 3-5 mm. wide, sometimes with rough margins and nerves beneath: 

 umbel simple, of usually 8 slender rays: spikes narrowly obovoid, 1-1.5 cm. 

 long: spikelets densely crowded, subulate, 3 mm. long, the lower ones becoming 

 reflexed: scales oblong or nearly so, 2.5-3 mm. long, ribbed, closely appressed: 

 achenes oblong-prismatic, nearly 2 mm. long, light-brown. — Pinelands. 



11. C. Poliardi Britton. Perennial, 6-13 dm. tall: leaves shorter than the 

 scape; blades usually less than 3 mm. wide: umbel of few unequally peduucled 

 heads: spikelets 3-4.5 mm. long, the scales loose, or deciduous at maturity: 

 achenes linear-oblong, about 1.5 mm. long. — Everglades and hammocks. — 

 {Cuba.) 



12. C. Torreyi Britton. Perennial by corms, 1-5 dm. tall: leaf -blades 2-3 

 mm. wide: umbel simple, the rays short, or the longer 2-7 cm. long: spikes 

 very dense, cylindric, 5-15 mm. long, 4-8 mm. in diameter, simple: spikelets 

 3-4 mm. long, flattish, 1-2-flowered, spreading or the lower reflexed: scales 

 green, oblong: achenes linear-oblong about 1.5 mm. long, apiculate, slightly 

 more than A as long as the scale. — Pinelands. 



13. C. tetragonus Ell. Perennial, 3-8 dm. tall: leaves mostly overtopped by 

 the sc^pe; blades 4-10 mm. broad, smooth or nearly so: umbel mostly com- 

 pound, of 6-12 slender erect or ascending rays and one or more spikes sessile 

 in the involucre: spikelets linear-oblong, plump, 4-6 mm. long, acute, chestnut- 

 colored, 4-6-flowered, spreading or the lower reflexed : scales oblong, fully 3 

 mm. long, 9-11-nerved, closely imbricate: achenes oblong or elliptic, 2 mm. 

 long, chestnut-colored, dull. — Everglades. 



14. C. ligularis L. Perennial, 5-12 dm. tall : leaves sometimes overtopping 

 the scape; sheath colored at the base; blades 6-20 mm. broad, serrulate, 

 somewhat revolute : umbel compound, of 6-many short rays, often rather 

 dense, or the rays rarely elongate: spikes cylindric or oblong, 1-2 cm. long: 

 spikelets 4-6 mm. long, gray to brown, densely crowded, spreading; scales 



