174 CYPERACEAE 



67. Cyperus Blodg6ttii Torr. Perennial, bright green. Leaves overtopped by the 

 scapes ; blades 2-4 mm. wide, smooth : scapes tufted, 1-3 dm. tall, 3-angled, smooth : bracts 

 of the involucre 3 or sometimes 2 very small additional ones present, the longer ones sur- 

 passing the umbel : umbel capitate or with one to three short rays : spikes 10-15 mm. in 

 diameter: spikelets 20-40, oblong or linear-oblong, 6-8 mm. long, densely crowded, 1-10- 

 flowered : scales oval to ovate, less than 2 mm. long, mostly 9-nerved, rather obtuse : 

 achenes 3-angled, oblong, about 1 mm. long, brown, dull. 



In sand, Key West, Florida. Spring to winter. 



68. Cyperus ligularis L. Perennial, glaucous. Leaves sometimes overtopping the 

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

 scapes erect, 5-12 dm. tall, 3-angled, smooth : bracts of the involucre 3-6, several much 

 elongated : umbel compound, of 6-many short rays, often rather dense, or the rays rarely 

 elongated : spikes cylindric or oblong, 1-2 cm. long : spikelets 4-6 mm. long, gray to 

 brown, densely crowded, spreading ; scales oval, 2.5-3 mm. long, blunt, closely imbricated 

 delicately ribbed : achenes 3-angled, elliptic or slightly broadest above the middle, 1.5 mm. 

 long, dark brown, dull. 



In sand or swamps, Florida. Also in the tropics of both hemispheres. Spring to winter. 



69. Cyperus Grayi Torr. Perennial by thick, hard oblong or ovoid corms. Leaves 

 shorter than the scape, bright green ; blades 2 mm. wide or less : scapes tufted, ascending 

 or reclined, stiff, smooth, very slender, 15-50 cm. long : bracts of the involucre 4-8 : 

 umbel 4-10-rayed, simple, the longer rays 7-10 cm. long : sheaths of the rays truncate or 

 nearly so : spikelets 5-10 mm. long, loosely capitate, compressed, linear, rigid, spreading : 

 scales green, ovate, obtuse or subacute, strongly 13-15-nerved, rather widely spreading 

 when old : joints of the rachis broadly winged : stigmas 3 : achene oblong or oblong- 

 obovoid, barely 2 mm. long, obtuse, apiculate. 



In sands of the sea shore and in pine lands, New Hampshire to Florida. Summer and fall. 



70. Cyperus echinatus ( Ell. ) Wood. Perennial by tuber-like corms. Leaves pale 

 green ; blades 3-4 mm. wide : scape slender, smooth, erect, mostly longer than the leaves : 

 bracts of the involucre 5-10, the longer usually much exceeding the umbel : umbel 6-13- 

 rayed : rays filiform, their sheaths short, mucronate : spikelets 4-8 mm. long, linear, flat, 

 capitate in globose heads : scales thin, pale green, appressed, ovate-lanceolate, acute, 9-13- 

 nerved, with narrow scarious margins : joints of the rachis broadly winged : stigmas 3 : 

 achene oblong-obovoid, 2 mm. long, about twice as long as thick. 



In dry or sandy soil, North Carolina to Missouri, Florida and Texas. Summer. 



71. Cyperus brunneus Sw. Perennial, bright green. Leaves overtopped by the 

 scape ; blades 2-7 mm. wide, smooth, sometimes involute : scapes erect, usually solitary, 

 3-7 dm. tall, 3-angled, smooth : bracts of the involucre often 4-5, all of them or the longer 

 ones surpassing the umbel, spreading : umbel compound, capitate, or 3-5 of the rays 

 becoming 1-5 cm. long : spikelets linear or linear-lanceolate, 10-15 mm. long, chestnut- 

 colored, densely crowded : scales oval or ovate-oval, nearly 3 mm. long, often apiculate, 

 conspicuously ribbed : achenes 3-angled, elliptic-obovoid, fully 1.5 mm. long, dark-brown, 

 granular. 



In sand, Florida. Also in tropical America. Spring to fall. 



72. Cyperus Ottonis Boeckl. Perennial, bright green. Leaves mostly overtopping 

 the scape; blades 4-12 mm. wide, with rough margins: scapes 3-12 dm. tall, 3-angled, 

 smooth : bracts of the involucre usually 5 or 6, several conspicuously elongated : umbel 

 compound, of 4-8 rays and 1 or more spikes sessile in the involucre : spikelets linear, 

 1-1.5 cm. long, chestnut-colored, numerous, often crowded, 10-16-flowered : scales oblong 

 or nearly so, fully 3 mm. long, acute, many-ribbed on the back, rather loosely imbricated : 

 achenes 3-angled, oblong-obovoid, fully 1.5 mm. long, dark brown, dull. 



In wet sand, Florida and the West Indies. Spring to fall. 



5. KYLLINGA Rottb. 



Annual or perennial sedges, with slender triangular scapes bearing 2 or more bracts at 

 the summit which form an involucre to the strictly sessile simple or compound, dense head 

 of spikelets. Spikelets numerous, compressed, each with 1 perfect flower, falling away 

 from the axis of the head at maturity, consisting of only 3 or 4 scales, the 1 or 2 lower 

 ones small and empty, the middle one fertile, the upper empty or staminate. Scales 2- 

 ranked, keeled. Perianth none. Stamens 1-3. Style deciduous from the summit of the 

 achene. Stigmas 2-3. Achene lenticular or 3-angied. 



Upper scales of the spikelets with scabrous or ciliate keels. 



Involucre with all the bracts spreading : upper scales of the spikelet scabrous. 1. K. pumila. 



Involucre with one bract erect : upper scales of the spikelet serrulate-ciliate. 2. K. brevifolia, 

 Upper scales of the spikelet with smooth keels. 3. K. odorata. 



