284 CYPERACEAE 



Ligule very short; scales reddish-brown-tinged. ,, , , , . , , , , 



Perigynia flat and nerveless or nearly so ventrally, the body sparingly serrulate above, contracted 



into beak --• '^^ ''-'^'^aria. 



Perigynia low-convex and strongly nerved ventrally, the body strongly serrulate above, abruptly 



contracted into the beak. , . , , . • . -^[ ^- ^/''^li'^"}''l'^\ 



Perigynia 2.25-3.25 mm. long; pistillate scales strongly awned; beak of perigynium about length ot body. 

 Leaf-blades shorter than culm, little roughened. 24. C. dudleyi. 



Leaf-blades e.xceeding culms, very rough. 2o. C. rulpmotdea. 



12. Paniculatae. 



Leaf-blades 1-2.5 mm. wide; head little interrupted; perigynia 2-2.75 mm. long, shining, not concealed by the 

 scales; sheaths not copper-tinged at mouth. . . , , , ^^•„''- ''""'^,''"j , ^.u 



Leaf-blades 2.5-6 mm. wide; head interrupted, compound; perigynia 3-4 mm. long, dull, concealed by the 

 scales; sheaths copper-tinged at mouth. 27. C. cusickn. 



13. Stenorhynchae. 



Perievnia 3-4 mm. long, the beak much shorter than the body; scales strongly dark-tinged. 



Leaves clustered at base; sheaths not green and white-mottled dorsally; culms slender; perigynia spongy 



at base 28. C. jonesii. 



Leaves not clustered at base; sheaths green and white-mottled dorsally; culms thick at base, strongly 



aphyllopodic. ' , , j ^ . .,1. • • 



Sheaths not cross-rugulose ventrally, concave or truncate and not prolonged at mouth; perigynia 

 " strongly spongy at base, sharply bidentate; stigmas long; culms weak. 29. C. nervina. 



Sheaths cross-rugulose ventrallv, convex and prolonged at mouth; perigynia little spongy at base, very 

 shallowly bidentate; stigmas short; culms not weak. ^ ^0- V- "ejirophora. 



Periffvnia 4-6 mm. long, the beak about equaling or longer than the body; scales not dark-tinged. 



°-' 31. C. stipata. 



14. Stellulatae. 



Spikes in a small (6-10 mm. long) densely capitate brownish-black head. 32. C. illota. 



Suikes more or less widely separate, not brownish-black. ,,/-,-,■ 



Beak of perigj-nium with few weak serrulations, the body broadest near middle. 33. C. laeviciilmis. 



Beak of perig\-nium strongly serrulate, the body broadest near base. , , , , , . , r , 



Beak of perigvnium bluntlv bidentate, one-fourth to one-third length of body, the ventral false suture 



obsolete or 'inconspicuous; scale obtuse, half length of body of perigynium. 34. C. interior. 

 Beak of perigynium sharply bidentate, the ventral false suture conspicuous. _ 



Culms obtusely triangular; beak of perigynium chestnut-brown-tipped; pistillate scales obtuse or 

 obtusish, chestnut-brown-tinged with broad shining margins and apex, rounded on back and 

 not sharply keeled, the midvein obscure at apex. 

 Suikes widely separate, the terminal long-clavate; perigynia 3.5-4 mm. long^ 

 •^ - J f 3 J (^ ormantha. 



Spikes approximate, the terminal short-clavate; perigynia 3.75-4.5 mm. long. 

 ^ '' 36. C . phyllotnanica. 



Culms sharplv triangular; beak of perigynium reddish-brown-tipped;- pistillate scales obtusish to 

 cuspidate, yellowish-brown-tinged, the margins and apex narrow, opaque or dull whitish, the 

 back keeled with the sharp midvein which is prominent to apex. , r - , j 



Perigynia lanceolate, the beak more than half length of body obscurely serrulate; leaf-blades 



0.75-2 mm. wide. , , ^' 'Ai V'^"fr%\ 



Perigynia ovate, the beak much shorter than the body strongly serrulate; leaf-blades 1.5-2 5 mm. 

 .■%' 38. C. cephalantha. 



w iQe. 



15. Deweyanae. 



Perigynia shallowly bidentate, 3.5-4 mm. long, the beak about one-third the length of the ^^^\ ^^ ^^^ 

 Perigj-nia deeply bidentate, 4-4.5 mm. long, the beak about one-half the length of the body.^ holanderi. 



16. OVALES. 



^°l^^^r^irS"u:)^-h;^:^T^^I,Suely cleft, bidentulate; lowest bract "ot^ appearing^like^^a^on- 

 Bearof'perigynium'"fe"ruginous at apex, bidentate; lowest bract appearing like a '^°-^t2'."c''Z7aLra//r'"'' 



Lower bracts not leaflet-like, from much shorter than to slightly exceeding head. 



Sheaths green-striate opposite blades, except at mouth; perigynia and scales light green. ^ ^^^^ 



''Ih'eltt st"oi^;gl;"prrngel upward at mouth opposite blade in a quickly ruptured vep membranaceous 



- Upr;"shllths''ulTa'^t)'conrave"of mln^aie at mouth opposite blades, not quickly ruptured." 

 I Beak of perigynium flat and serrulate to the often strongly bidentate tip. 



Perigvnia subulate to lanceolate, at least two and one-half times as long as wide. 



Perig\nia subulate, the margin at the base almost obsolete. 45. L. aawjoiaii. 



Perigynia lanceolate, the margin conspicuous to the base. 40. c. scopana. 



Perigynia lanceolate-ovate or broader, at most twice as long as wide. 

 Perigynia narrowly to broadlv ovate, 3-4 mm. long. 



Perigynia brownish; spikes closely aggregated, rounded at base. u.ku" 



Culms rough above; perigynia with beak flattened to tip. 47. C. oebb' ■ 



Culms smooth; perig>'nia with beak subterete towards tip. 67. L subtusca. 



Perigynia green; spikes contigtious to widely separate, usually clava^e ^^.^^^'^^•^^^ 



Perigynia averaging 4-8.5 mm. long: or if shorter with orbicular bodies. , ■ 

 Scales little if at all reddish-brown-tmged. . 4y. l. oie.iyr. 



Scales stronelv reddish-brown- or chestnut-brown-tinged. . , , . 



Perig^nL membranaceous, flattened, concave-convex with wide thm margins con- 

 spicuously crinkled dorsally; scales with light slender ntidve.m ^ ^^,.^,,^^.„.^^^„„.^ 



Perigynia subcoriaceous, plano-convex and thick with na"°^er margins not crinkled 

 dorsally; scales with light 3-nerved center. ^ Vi =n il.en? iA C 



IL Beak of perigynium terete towards apex; the upper 1-3 mm. smooth or nearly so (except m C. 

 snbfusca and C. prcsHi). , ^ . , - ,^ 



Perigynia lanceolate, 5.5-8.5 mm. long, three to five times as long as wide^ 

 _ Scales about length and width of perigynia and largely concealing them. ^ ^^^^^^^^ 



