562 CYPEKACE^. 



CXXXVI. CYPEEACEJ;. 



Flowers in spikeleta, naked : the sexual organs oftea supported by bristles or scales, en- 

 ■tilosed by glumaceous bracts (glumes) : bracts usually single at each flower. Stamens often 3, 

 hypoijynoas. Ovary simple : ovule single, erect : style 2-3-cleft. Pericarp utricular. 

 Emlryo trochleate, included within the summit of amylaceous albumen. — Habit of grasses, 

 lut stem solid, devoid of tumid nodes, leaves tristichous, and their sheath mostly closed. 



TaiBE I. CYPEEEM. — Flowers disiichoits, hermaphrodite. 



1. CYPEKUS, L. 



Spikelets many-few-flowereJ : 1-2 lowest glumes empty : rhachis furrowed, often winged 

 ' at each intemode by the decurrent, at leugth lacerate part of the glumes. Achenium beak- 

 less. — Spikelets clustered or spikate, rarely solitary : the clusters often in a simple or com- 

 pound, terminal, involucrate umhel. 



The description of the form of the glumes regards their conduplicate, keeled state, viz. one- 

 half of their entire breadth. 



Sect. 1. PiCMUS, P. jB. — Spikelets compound: furrows narrowly winged : glumes 

 keeled. Style %-cleft. Achenium laterally compressed. 



1. C. polystachyus, Rottb. Bhizoma short; stem 3-angular, glabrous; umbel 

 usually contracted: involucre long, . 3-6-leaved ; spikelets densely clustered, lanceolate, 

 ^oiBterf, usually p«?e, many (-8) -flowered; glumes etlipiical-lanceolate, bluntish, Z-nerved 

 at the keel with the midrib excurrent, 4-3 times as long as the furrow, twice as long as the 

 oblong achenium ; stamens 2-1. — Bottb. Descr. t. 11. /. 1. — Stem 1' (8"-2') high, naked 

 above, usually exceeding the flat leaves ; glumes 1'" long. — Hab. Jamaica !, P^^., in moist 



• places; Antigua!, Wullschl. ; Trinidad!, Cr. ; [all tropical countries to Australia!, the 

 Cape !, Algeria!, and the hot springs of Ischia !]. 



^ 2. C. variegatus, Kth. Bhizoma short ; stem 3-angular, glabrous : clusters in an unequal 

 or contracted umbel; involucre long, 3-leaved ; spikelets ovate-oblong or oblong-lanceolate, 

 bluntish, either pale or blackish, 14-8(-" 24 ")-flowered ; glumes half -ovate-oblong, blunt, 

 few-nerved at the keel, 4-5 times as long as the furrow, 2i times as long as the elliptical 

 achenium; stamens 2(-l). — C. melanostachyus, Kth.: the blackish, C. flavus, Prl.: the 

 yellowish-flowered form, of which the latter is our Jamaica plant, while the former exists iu 

 Swartz's West Indian herbarium.— 6"-18" high; glumes ]"'.long. — Hab. Jamaica !, ft/., 

 in the plains of Westmoreland ; [Haiti 1 Mexico to Costarica!, New Granada]. 



Sect. 2. JUNCELius. — pikelets compressed : glumes keeled: farrows narrowly margined. 

 Style %-eleft. Achenium compressed from the back. 



3. C. mucronatus, MoUb. Khizoma creeping ; stem cylindrical below, glabrous, 1- 

 leaved (or naked) ; cluster single : involucre unequally l-rayed : the longer ray erect, the 

 inferior shorter than the cluster ; spikelets oblong or ovate, bluntish, pale, many (-6)-flowered ; 

 glumes half-ovate, blunt, 3-4 times as long as the furrow, twice as long as the oval ache- 

 nium ; stamens 3. — Sottb. Descr. t. 8./. 4. — li'-6" high; leaves narrow; glumes 1'" 

 long. — Hab. Antigua !, Wullschl. ; [all tropical countries to Egypt and Pantellaria I]. 



Sect. 3. EuoyPERUS, iieim. — Spikelets compressed or subcompressed : glumes keeled: 

 rhachis persistent. Style Z-c!eft. Achenium Z-angular. 



/ * Boot annual. 



Y' 4. C. compressus, L. Annual; stem 3-angular, glabrous; clusters umbellate (or 

 t single) : involucre long, 3-6-leaved ; spikelets flat-compressed, oblong-linear, pointed, pale, 

 f , niany(-6)-tlowered; glumes half-ovate-oblong, cuspidate with a spreading-ereet point, sharply 

 ' keeled, many-nerved, winged, 4-5 times as long as the furrow, thrice as long as the obovate, 

 3-quetrous, smooth achenium ; stamens 3. — SI. t. 76. /. 1. Rottb. Descr. t. 9. /. 3. — 

 4"-12" highs leaves narrow, flat, rarely setaceous ; glumes li"' long.— Hab. Jamaica!, 



