CYPERACEAE. 45 



2. Cyperus cuspidatus H.B.K. Nov. Gen. 1: 201. 1816. 



Annual, glabrous; culms tufted, 2-14 em. tall, as long as the leaves, or 

 longer. Leaves 1-2 mm. wide, those of the umbel usually 3 or 4, sometimes 1 

 dm. long; umbel 2-5-rayed, rarely capitate; rays 0.5-5 cm. long; spikelets 

 linear, 5-12 mm. long, about 1.5 mm. wide, digitate, many-flowered; scales 

 chestnut-brown, nearly 2 mm. long, strongly 3-5-nerved, keeled, the recurved- 

 spreading awn-like tip nearly as long as the body; stamens 1-3; achene broadly 

 obovoid, 0.5 mm. long, trigonous, brown, apiculate; style very short. 



Wet soil, New Providence, Cat Island, Fortune Island, Acklin's Island, South 

 Caicos, Inagua : southern United States : Cuba ; Anegada ; Yucatan ; South Amer- 

 ica. Recorded by Hitchcock as C. aristutus Rottb. CUSPIDATE CYPE.RUS. 



3. Cyperus compressus L. Sp. PI. 46. 1753. 



Annual; culms slender, erect or reclining, smooth, 7-25 cm. long. Leaves 

 light green, about 2 mm. wide, those of the involucre 2-3, the longer exceed- 

 ing the spikelets; umbel capitate or with 2-3 short rays; spikelets narrowly 

 lanceolate, acute, 8-20 mm. long, 3-4 mm. wide, very flat, many-flowered; 

 scales light green with a yellow band on each side, ovate, acuminate, firm, 

 keeled, several-nerved, falling away from the narrowly-winged rachis at ma- 

 turity; stamens 3; style 3-cleft; achene sharply 3-angled, obovoid, obtuse, dull, 

 brown, about one-third as long as the scale. 



Waste grounds, New Providence : United States ; Cuba to Virgin Gorda and 

 Trinidad; Jamaica; tropical continental America and Old World tropics. FLAT 

 CYPEKUS. 



4. Cyperus ochraceus "Vahl, Enum. 2: 325. 1806. 



Perennial; culms rather stout, 2-7 dm. tall. Leaves 6 mm. wide or less, 

 the basal ones mostly shorter than the culm, those of the involucre several, 

 spreading, 2 or more of them much longer than the compound or simple umbel; 

 umbel-rays 15 cm. long or less; spikelets numerous, capitate, flattish, blunt, 

 many-flowered, 5-12 mm. long, about 2 mm. wide ; scales yellow, ovate to ovate- 

 lanceolate, obtusish ; stamen 1 ; achene ovoid, 3-angled, narrowed at both ends. 



Swamps, New Providence: southern United States; Cuba to Guadaloupe; Ja- 

 maica ; tropical continental America. Erroneously referred by Clarke to C. Luzulae 

 Rottb., citing Brace no. 408 ; referred also here by Dolley. YELLOW CYPERUS. 



5. Cyperus pseudovegetus Steud. Syn. PI. Cyp. 24. 1855. 



Perennial by thickened tuber-like joints of the rootstocks; culm rather 

 stout, 0.3-1.3 m. high, often equalled by the leaves. Leaves 3-4 mm. wide, 

 smooth, nodulose, the midvein prominent; leaves of the involucre 4-6, spread- 

 ing; umbel several-rayed, compound; spikelets ovate, flat, many-flowered, light 

 green, densely capitate, 4-6 mm. long; scales keeled, conduplicate, 1-nerved, 

 curved, acute, longer than the linear 3-angled slightly stalked achene; stamen 

 1; style 3-cleft. 



Swamps. New Providence at Southwest Bay : southeastern United States. 

 MARSH CYPERUS. 



6. Cyperus elegans L. Sp. PI. 45. 1753. 



Cyperus viscosus Sw. Prodr. 20. 1788. 



Perennial by short rootstocks ; culms viscid-pubescent, 8 dm. tall or less. 

 Leaves convolute in drying, the basal ones about as long as the culm, those of 

 the involucre about 3, the longer ones much surpassing the inflorescence; umbel 

 usually compound, the rays up to 15 em. long; spikelets 2-12 in the clusters, 

 digitate, oblong-lanceolate, 6-15 mm. long, 3-5 mm. wide, compressed; scales 

 green-brown, ovate, strongly mucronate, about 3 mm. long; stamens and style- 

 branches 3 ; achene obovoid, 3-angled, nearly black, about half as long as the 

 scale. 



Marshes and sink-holes, Great Bahama. New Providence, Eleuthera, Cat Island, 

 Watling's Island, Acklin's Isand, Great Exumn, Inagua : Florida ; Cuba to St. 

 Jan and Trinidad ; Jamaica ; Yucatan ; South America. VISCID CYPERUS. 



