508 CYPERACE^E. (3EDOE FAMILY.) 



in dense tufts. Culms triangular, bcaiing the spikes in the axils of green and 

 leaf-like or scale-like bracts ; commonly with thin membranaceous sheaths at 

 the- base which enclose more or less of the stalks of the spikes. Leaves grassy, 

 usually rough on the margins and keel. (A classical name, of obscure signifi- 

 cation ; derived by some from careo, to want, the upper spikes being mostly 

 sterile ; and by others from Kctpu, to cut, on account of the sharp leaves.) 



ABRIDGED SYNOPSIS OF THE SECTIONS. 



A. Spike solitary, simple, dioecious or androgynous : bracts small, colored and scale-like __ 



(This division, retained for the convenience of students, is merely artificial, and combines 

 species having no real natural affinity.) PSYLLOPIIOOS, Loisel 

 i 1. Spike dioecious, or with a few staniinate flowers at its base. No. 1-3. 

 2. Spike androgynous, staniinate at the summit. No 4-7. 



B. Spike solitary, single, androgynous, staminate at the summit : bracts and scales of the fer- 



tile flowers green and leaf-like. Stigmas 3. - PIIYLLOSTAC1I YS, Torr. & Gr. No. 8 -10. 



C. Spikes several or numerous, androgynous (occasionally dioecious in No. 11 and 33), sessile, 



forming compact, or more or less interrupted, sometimes paniculate, compound or de- 



compound spikes. Stigmas 2 V1GNEA, Beauv. 



j 1. Spikes approximate, with staminate and pistillate flowers variously situated. No. 11 - 1&. 

 2. Spikes pistillate below, staminate at the summit. No 14 28. 

 8. Spikes pistillate above, staminate at i he base No. 29-41. 



D. Staminate and pistillate flowers borne in separate (commonly more or less stalked) simple 



spikes on the same culm ; the one or more staminate (sterile) spikes constantly upper- 

 most, having occasionally more or less fertile flowers intermixed ; the lower spikes all 

 pistillate (fertile) or sometimes with staminate flowers at the base or apex. Stigmas 3 (or 

 only 2 in No. 42-49 and 58). CAKEX PROPER. 



* Perigyuia with merely a minute or short point, not prolonged into a beak. 

 $ 1. Perigynia not inflated (slightly so in No. 51), smooth, nerved or nerveless, with a minute 

 straight point ; glaucous-green, becoming whitish, or more or less spotted or tinged with 

 purple. Scales blackish-purple or brown. Staminate spikes 1 - 3, or the terminal spike 

 androgynous and staminate at the base, the rest all fertile. No 42-57. 



2. Perigyuia slightly inflated, smooth, nerved, obtuse and pointless or with a straight or 

 oblique point. Scales brown, becoming tawny or white. Staminate spike solitary (ex- 

 cept sometimes in No. 62) or androgynous and pistillate above, the rest all fertile. No. 

 58 - 71. 



3. Perigynia slightly inflated, hairy (in No. 70 smooth at maturity), nerved, with a minute 

 straight point. Terminal spike androgynous, pistillate at the apex, the rest all fertile. 

 No 72, 73. 



4 Perigynia not inflated, smooth, regularly striate, with a short, entire, obliquely bent or 

 recurved point, remaining green at maturity. Staminate spike solitary. Bracts green 

 and leaf-like (except in No. 74). No 74 - 81 



6. Perigynia not inflated, smooth or downy, not striate, with a minute, obliquely bent, white 

 and membranaceous point, reddish-brown or olive-colored at maturity. Terminal spike 

 all staminate, or with 2-3 fertile flowers at the base ; the rest all fertile, or with a few 

 sterile flowers at the apex. Bracts reduced to colored sheaths, or with a short green pro- 

 longation. No. 82, 83. 



* * Perigynia with a distinct beak, either short and abrupt, or more or less prolonged. 



Perigynia not inflated, hairy, with a rather abrupt beak, terminating in a memhramv- 

 ceous notched or 2-toothed orifice Bracts short : culms mostly low and slender ; leaves 

 all radical, long and narrow Staminate spike solitary. No 84-90. 



7. Perigynia slightly inflated, hairy or smooth, with a short )>e.ak terminating in an enMre 

 or slightly notched orifice- I'.rarts long and leaf-like: culms till and leafy. Stamiriatu 

 eplk* solitary (in No 91 pistillate at the summit) : fertile spikes em t (except in No. 91), 

 No. 91 -93. 



