336 



CYPERACE.E. 



Group 6. Flowers imbricated with bracts ( glumes, scales ), and disposed in spikelets; 

 but with no proper jloral envelopes or perianth, except in the form of bristles 

 or scales. Ovary one-celled, with a solitary ovule ; in fruit, an achenium or 

 caryopsis. Embryo at the extremity of the albumen next the hilum. — ■ Grasses, 

 sedges, or rush-like plants. 



Order CXXIV. CYPERACEiE. Juss. The Sedge Tribe. 



Flowers often monoecious or dioecious ; one in the axis of each scale. Perianth 

 none, or consisting of bristles or scales. Stamens mostly 3, hypogynous. Styles 

 2 or 3, mostly united. Fruit an achenium. — Culms usually solid, and often 

 triangular. Sheaths of the leaves entire. 



CONSPECTUS OF THE TRIBES AND GENERA. 

 Tribe 1. CYPEREjE. Flowers perfect. Spikelets distichously imbricated. 



1. Dulichium. Bristles of the perigynium 6-9. 



2. CyrERtrs. Bristles none. 



Tribe 2. FUIRENEiE. Flowers perfect. Scales imbricated on all sides. Perigynium of three scales or 

 leaflets, often alternating with three bristles. Stamens 3. Stigmas 3. 



3. Fuirena. Character that of the tribe. 



Tribe 3. SCIRPEiE. Flowers perfect. Scales imbricated on all sides (rarely bi-trifarious). Perigynium 

 composed of bristles, hairs or scales, sometimes wanting. 



4. Eleocharis. Achenium with bristles at the base, crowned with the bulbous base of the style. 



5. Scirpus. Style simple at the base. Achenium surrounded with bristles. 



6. Eriophorum. Style simple at the base. Achenium surrounded with very long (usually numerous) capillary hairs. 



7. Fimbristylis. Style 2-cleft, compressed and dilated at the base, deciduous. Bristles none. 



8. Isolepis. Style simple at the base or somewhat bulbous, deciduous. Bristles none. 



9. Trichelostylis. Style 3-cleft, more or less bulbous at the base, deciduous. Bristles none. 



Tribe 4. HYPOLYTREjE. Flowers perfect. Scales of the spikes imbricated on all sides, each one- 

 flowered ; the flowers with a 1 - 4-valved perigynium. 



10. Hemicarpha. Spikes ovoid ; the scales very numerous. Flowers with a single valve, which is sometimes adherent 



to the fruit. Stamen single. Style 2-cleft. Achenium oblong, biconvex or nearly terete. 



Tribe 5. RHYNCHOSPOREiE. Flowers perfect or polygamous. Spikes mostly few-flowered ; the scales 

 irregularly imbricated. Perigynium usually setiform, rarely wanting. Achenium crowned with 

 the beaked or articulated base of the style, mostly corrugated. 



11. Rhynchospoha. Spikes few-flowered ; I he lower scales empty or staminate. Perigynium of 6 or more plumose or 



rough bristles. Achenium crowned with the articulated persistent base of the style. 



Tribe 6. CLADIEiE. Flowers usually perfect. Scales of the spike irregularly imbricated : one or several 

 of the upper ones fertile ; the others empty. 



12. Cladium. Spike few-flowered. Bristles none. Stamens 2. Achenium subglobose ; the pericarp thickened and corky 



towards the summit. 



Tribe 7. SCLERIEjE. Flowers diclinous. Fertile spikelets one- or rarely 2-flowered. Scales fasciculate; 



the lower ones empty. Perigynium of 3 scales, distinct from the disk or combined with it, often 

 wanting. Achenium with a bony or crustaceous shell, often seated in a cup-shaped or lobed disk. 



13. Scleria. Fertile spikelets one-flowered. Achenium globose or ovoid. Disk lobed, annular, or nearly wanting. 



Tribe 8. CARICEiE. Flowers diclinous. Scales of the spikes membranaceous, imbricated on all sides. 

 Achenium wholly enclosed in an urccolate perigynium, which is pervious at the summit. 



14. Carex. Fertile flowers destitute of a setiform appendage. 



