Oyperus.~\ cyperaceje. 
Subgenus Cyperus proper. Stigmas 3. Achenes triquetrous, 
407 
Spikelets sessile in a single terminal head. 
Spikelets 3-5. Glumes dark-brown 9. 
Spikelets 20-40. Glumes drab 10. 
Spikelets in a simple umbel. 
Annual. Glumes drab-brown. 
Glumes small, obtuse. Leaves setaceous . . .11. 
Glumes large, acute. Leaves linear 12. 
Perennial, stoloniferous. Glumes bright red-brown. 
Spikelets •§— £ in. long 13. 
Spikelets £-1 in. long 14. 
Spikelets in a compound umbel. 
Glumes bright reddish-brown. 
Annual, with imbricated glumes .... 
Perennial, with imbricated glumes . . . 
Perennial, with distant glumes . . 
Glumes drab- or greenish-brown, rarely darker. 
C. EXILIS. 
C. DUBIUS. 
C. MICROLEPIS. 
C. COMPRESSUS. 
C. TUBEROSUS. 
C. ROTUNDU8. 
15. 
16. 
17. 
Glumes 
in. long. 
4-8 31 - 
Spikelets in globose heads 
Spikelets not congested in heads 
18. 
19. 
C. AMABILIS. 
C. LONGUS. 
C. DISTANS. 
C. DIFFORMIS. 
C. Iria. 
Glumes in. long. 
Rays of primary umbel equal .... 
Rays of primary umbel very unequal. 
Stems leafless, distinctly articulated . . 
Stems leafy, not articulated. 
Leaves in. broad. 
Spikelets 6-10-flowered. 
Glumes ribbed on the sides . . 
Glumes ribbed on the keel only 
Spikelets 25-30-flowered . . . . 
Leaves in. broad 
Leaves an inch or more broad . . . 
20. C. JEQUALIS. 
21. C. ARTICULATUS. 
. 22. C. PENNATUS. 
. 23. C. pilosus. 
. 24. C. Gardneri. 
. 25. G. LON GIFOLIUS. 
. 26. C. LATIFOLIUS. 
1. C, lsevigatus, Linn. Mant. 179. Stems close or a space apart 
on a creeping rhizome, 6-18 inches high, terete, clasped by two mem- 
branous sheaths at the base, the top one usually produced into a short 
blade. Spikelets 6-20 in a dense sessile lateral cluster some distance 
from the top of the stem, bracteated by a single small linear leaf 5— f 
in. long, 12-30-flowered. Glumes ovate-deltoid, fa i n - l° n g> sub- 
obtuse, whitish, much imbricated. Achene plano-convex, bright brown, 
half as long as the glume. C. mucronatus, Rottb. ; Kunth , j Enum. 
ii. 17. 
Mauritius and Rodriguez, in swamps through the islands. Warmer regions of 
both hemispheres. There is a very depauperated form in Dr. Balfour’s Rodriguez 
collection with solitary spikelets and stems 2-3 inches long. 
2. C. pygmaeus, Rottb.; Kunth. Enum. ii. 18. Annual. Stems 
densely tufted, 2-3 in. long, triquetrous. Leaves linear, acutely 
keeled, as long as the stems. Spikelets very numerous, i in. long, crowded 
into a globose terminal head, bracteated by 6-8 linear leaves 1-3 
in. long, 20-30-flowered. Glumes lanceolate, acuminate, greenish. 
