406 
CYPERACEiE. 
Tribe II. Scirpeje. Glumes multifarious. Flowers many in a spike- 
let, hermaphrodite. Achenes naked. 
Hypogyiious bristles 0. 
Spikelets solitary 
Spikelets panicled 
Perianth of bristles. 
Spikelets solitary 
Spikelets clustered . 
Perianth of navicular scales. 
Spikelets in a sessile head. Stamen 1 . . . 
Spikelets crowded in heads, mostly panicled . 
Spikelets in a lax corymbose panicle . . . 
7. Isolepis. 
8. Fimbristylis, 
9. Eleocharis. 
10. Scirpus. 
11. Lipocarpha. 
12. Fuirena. 
13. Hypolytrum. 
Tribe III. Ehyncho spores. Glumes multifarious. Flowers 1-2 
in a spikelet, usually hermaphrodite. Achenes naked. 
Some of the flowers hermaphrodite. Achenes minute. 
Hypogynous bristles 0. Style trifid 14. Cladium. 
Hypogynous bristles present. Style bifid . . . .15. Bhynchospora. 
All the flowers unisexual. Achenes large, glossy . . .16. Scleria. 
Tribe IV. Caricinea:. Glumes multifarious. Flowers all unisexual. 
Achenes enclosed in a bottle-shaped utricle. 
The only genus 17. Carex. 
1. CYPERUS, Linn. 
Flowers hermaphrodite, arranged in distichous many-flowered spike- 
lets. Glumes boat-shaped, usually much imbricated, all except the 
lowest fertile. Hypogynous bristles 0. Stamens usually 3, rarely 
1 or 2. Style trifid and achene triquetrous (. JEucyperus ), or style bifid 
and achene plano-convex ( Pycreus ). — Perennial or annual herbs, with 
sheathing grass-like leaves (sheaths rarely not produced into a blade), 
usually triquetrous stems, spikes usually very numerous, arranged in 
simple or compound umbels, rarely congested into a single head. 
Distrib. Cosmopolitan in the tropical and warmer temperate zones. 
Species 300. 
Subgenus Pycreus. Stigmas 2. Achenes plano-convex. 
Spikelets in a dense simple lateral head 1 . C. ljevigatus. 
Spikelets in a dense simple terminal head 2. C. pygmjeus. 
Spikelets in a simple terminal umbel. 
Glumes drab-brown. 
Annual ; involucre 3-leaved 3. C. globosus. 
Perennial ; involucre 5-6-leaved 4. C. polystachyus. 
Glumes bright red-brown. 
Involucre about 3-leaved, short. Glumes obtuse . 5. C. cruentus. 
Involucre 6-8-leaved, long. Glumes subacute . 6. C. ferrugineus. 
Spikelets in compound terminal umbels. 
Glumes drab-brown ; spikelets in. long . . . 7. C. Alopecuroides. 
Glumes bright red-brown ; spikelets in. long . 8. C. tremulus. 
