278 



CYPERACEAE 



1. Dulichium arundinaceum (L.) Britton. 



Dulichiuni. 



Fig. 668. 



Cyperus arundinaceus L. Sp. PI. 44. 1753. 



Cyperus spathaceus L. Syst. ed. 12, 2: 275. 1767. 



Dtilichinm spathaceum Pers. Syn. 1: 65. 1805. 



Dulichium arundinaceum Britton, Bull. Torrey Club 21: 

 29. 1894. 



Culm Stout, 0.3-1 m. tall, erect. Leaves 

 numerous, flat, 2-8 cm. long. 4-8 mm. wide, 

 spreading or ascending, the lower sheaths blade- 

 less, brown toward their summits ; peduncles 

 4-25 mm. long ; spikelets narrowly linear, spread- 

 ing, 1-2.5 cm. long, about 2 mm. wide, 6-12- 

 fiowered ; scales lanceolate, acuminate, strongly 

 several-nerved, appressed, brownish ; bristles of 

 the perianth rigid, longer than the achene ; style 

 long-exserted, persistent. 



Swamps, Transition Zone; Humboldt County, Cali- 

 fornia, to Oregon, British Columbia, east to Montana, 

 Nebraska, Texas, Florida, and Nova Scotia. Type local- 

 ity: Virginia. 



7. HEMICARPHA Xees & Arn: Edinb. New Phil. Journ. 17: 263. 1834. 



Low tufted mostly annual sedges, with erect or spreading, almost filiform culms and leaves, 

 and terete small terminal capitate or solitary spikelets subtended by a 1-3-leaved involucre. 

 Scales spirally imbricated, deciduous, all subtending perfect flowers. Perianth of a single 

 hyaline sepal (bract?) between the flower and the rachis of the spikelet ; bristles none. 

 Stamens 1-3. Style 2-cleft, deciduous, not swollen at the base. Achene oblong, turgid or 

 lenticular. [Greek, in allusion to the single sepal.] 



About 5 species, natives of temperate and tropical regions. Type species, Hcmicarpha isolcpis Nees. 



Scales short-tipped or niucronate. 

 Scales awned. 



Scales rhombic-obovate, abruptly awned. 



Scales lanceolate to ovate-lanceolate, narrowed above into the awn. 



1. H. micrantha. 



2. H. aristulata. 



3. H. occidentalis. 



1. Hemicarpha micrantha (\'ahl ) Pax. 

 Common Hemicarpha. Fig. 669. 



Scirpus micranthus Vahl, Enum. 2: 254. 1806. 



Hemicarpha stibsguarrosa Nees in Mart. Fl. Bras. 21 : 

 61. 1842. 



Hemicarpha micrantha Pax in E. & P. Nat. Pflf. 22: 105. 

 1887. 



Annual ; glabrous ; culms compressed, 

 grooved, 2-10 cm. long, mostly longer tiian the 

 setaceous smooth leaves. Spikelets ovoid, many- 

 flowered, obtuse, about 2 mm. long ; involucral 

 leaves usually much exceeding the spikelets ; 

 scales brown, obovate, with a short blunt 

 spreading or recurved tip ; stamen 1 ; achene 

 obovate-oblong, obtuse, mucronulate, little com- 

 pressed, light brown. 



Moist soil, Transition Zone; Tuolumne County, Cali- 

 fornia, north to Washington; east to Florida and New 

 Hampshire; West Indies; Mexico; continental tropical 

 America. Type locality: (?) South America. 



