CYPERACEX. (SEDGE FAMILY.) 505 
8. SCIRPUS. Tubercle none: culms mostly leafy at the base or throughout: spikes com- 
monly few or many : perianth of 3 — 6 bristles. 
9. ERIOPHORUM. Perianth of numerous long and woolly hairs: otherwise like Scirpus. 
* * * Perianth none: style tumid at the base. 
+ Scales imbricated in several rows : spikes terete. 
10. FIMBRISTYLIS. Style deciduous: stigmas 2: nut lenticular or globose. 
11. TRICHELOSTYLIS. Style deciduous: stigmas 3: nut 8-angled. 
12. ISOLEPIS. Style persistent at the base: stigmas 3: nut S-angled. 
+ + Scales imbricated in 2 rows: spike compressed. 
13. ABILGAARDIA. Style 3-cleft, jointed to the 3-angled nut. 
Troe IV. RHYNCHOSPORELKE. — Flowers perfect or polygamous: spikelets com- 
monly few-flowered : scales one to each flower, imbricated in few — several rows, the lower 
ones empty, the upper mostly sterile: perianth bristly, or none. 
* Perianth bristly (occasionally wanting in Rhynchospora). 
14. RHYNCHOSPORA. Style 2-cleft, dilated and persistent at the base: nut lenticular or 
globose. 
` 15. CERATOSCHENUS. Style entire or minutely 2-cleft, the lower half persistent : nut flat. 
16. CHÆTOSPORA. Style 3-cleft, deciduous: nut 3-angled : spikelets terminal. 
* * Perianth none. 
17. PSILOCARYA. Spikes terete, many-flowered, cymose : flowers perfect. 
18. DICHROMENA. Spikes compressed, capitate : most of the flowers imperfect. 
19% CLADIUM. Spikes few-flowered, only the uppermost flower perfect : nut globose. 
Terere V. SCLERIE. — Flowers monoecious : sterile spike many-flowered : Se dins 
to each flower, imbricated in furrows : fertile spike 1- > With two or more Stales : 
perianth none. 
20. SCLERIA. Style 3-cleft, deciduous. Nut bony, globose or 3-angled. 
Tre VI. CARICE AS. — Flowers monecious, very rarely dioecious: sterile and fertile 
flowers on the same spike, or on separate spikes: scales one to each flower, imbricated 
in few - many rows: nut enclosed in a sac: perianth none. 
21. CAREX. Bristles within the sac none. Spikes axillary and terminal. 
1. CYPERUS, L. 
Spikelets 2-many-flowered, commonly flat or compressed, Scales imbricated 
in two opposite rows, often decurrent on the jointed rachis, deciduous. Perianth 
none. Stamens 1-3. Style 2-3-cleft, deciduous. Nut lenticular or 3-angled. 
— Culms 3-angled (rarely terete), jointless, leafy or occasionally sheathed at 
the base. Spikelets numerous (rarely 1-2), disposed in single or umbellate 
heads or spikes, and surrounded with a leafy involucre. Rays sheathed. 
$1. PYCREUS. Style 2-left: nut lenticular : spikes Oe dae seatallad. 
Annuals : spikelets linear or linear-oblong, flat, many- (10 — 40-) Jlowered : 
rachis narrowly margined : scales compressed-keeled, 5-nerved. 
* Spikelets clustered on the common rachis. 
1. C. flavescens, L. Umbel sessile or of 2- -4 rays, shorter than the 
V rund: quitan 3.-several ina cluster, oblon; -line 
