508 CYPERACE^E. (SEDGE FAMILT.} 



in dense tufts. Culms triangular, bearing 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 Kei'pw, to cut, on account of the sharp leaves.) 



ABRIDGED SYNOPSIS OF THE SECTIONS. 



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



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

 species having no real natural affinity.) PSYLLOPHOR^E, Loisel. 

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

 2. Spike androgynous, staminate 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. - PHYLLOSTACHYS, 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. VIGNEA, Beauv. 

 $ 1. Spikes approximate, with staminate and pistillate flowers variously situated. No. 11 - 18. 



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



3. 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 PBOPER. 



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

 f 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. Perigynia 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 tew 

 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. 



6. Perigynia not inflated, hairy, with a rather abrupt beak, terminating in a membrana- 

 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 beak terminating in an entire 

 or slightly notched orifice Bracts long and leaf-like : culms tall and leafy. Staminats 

 spike solitary (in No 91 pistillate at the summit) : fertile spikes erect (except in No. 91). 

 No. 91 -93. 



