CYPERACEAE. 
67 
Spike dull-brown; perigynium erect or slightly spreading at maturity, obovate, 
shortly beaked or beakless, the orifice entire. 54. C. rupestris. 
Spike shining, reddish-brown; perigynium horizontally bent at maturity, turgid, 
coriaceous, obscurely nerved, the short beak with hyaline orifice. 
55. C. obtusata. 
20. Elynanthae. 
Spike single, androgynous, the pistillate portion few-flowered; scales very 
broad; perigynium membranaceous, whitish to brown, erect, sessile, oval to 
obovoid, pubescent or ciliate above, the beak short, with the orifice entire or 
obliquely cut; stigmata 3. 
Spike silvery-shining, light-brown ; perigynium oval, pubescent, the beak entire. 
56. C. dlifolia. 
Spike reddish-brown; perigynium obovoid, attenuated at both ends, the beak cili¬ 
ate, obliquely cut. 57. C. elynoides. 
21. Sphaeridiophorae. 
Spike one, the plant dioecious or monoecious, or several, the terminal 
staminate, the lateral pistillate; the latter few-flowered, roundish, mostly ses¬ 
sile or the basal long-peduncled; bracts foliaceous, sheathless; scales acu¬ 
minate, often mucronate, green to blackish; perigynium dark-green, stipitate 
or sessile, obovate to globose, pubescent, obscurely nerved, the beak mostly 
short, obliquely cut or bidentate, with the teeth erect; stigmata 3. 
Spikes solitary; beak short, obliquely cut. 
Dioecious; spike very dark, many-flowered; perigynium strigosely hairy, obo¬ 
vate to oval. 58. C. scirpoidea. 
Monoecious ; spike androgynous, silvery-shining; perigynium minutely pubescent, 
broadly elliptic. 59. C. oreocharis. 
Spikes several. 
Rhizome stoloniferous; spikes dark-colored, sessile or nearly so; perigynium 
globose, abruptly beaked; beak short, entire or 2-lobed. 60. C. pennsylvanica. 
Rhizome caespitose; spikes peduncled, light-green to brown. 
Perigynium oval, stipitate; beak bifid. 61. C. Rossii. 
Perigynium globose; beak long, obliquely cut. 62. C. umbellata. 
22 . TrICHOCARPAE. 
Spikes several, cylindrical, dense-flowered, sessile or the lowest one pedun¬ 
cled, but erect, remote, the terminal and uppermost lateral staminate, the 
others pistillate; bracts foliaceous, long and sheathing; scales purplish or 
brown, mucronate to aristate; perigynia erect, sessile, ovate to ovate-lanceo¬ 
late, turgid, more or less pubescent, nerved, the beak prominent, bidentate; 
stigmata 3. 
Perigynium ovate, densely pubescent. 63. C. lanuginosa. 
Perigynium ovate-lanceolate, sparingly pubescent, the beak with very long, diverg¬ 
ing teeth. *64. C. aristata. 
23. Hymenochlaenae. 
Spikes several, androgynous or the terminal staminate, the lateral pistil¬ 
late, not very dense-flowered, long-peduncled and drooping; bracts folia¬ 
ceous, sheathing; scales hyaline, mucronate; perigynia erect to slightly 
