480 THE SEDGE FAMILY. [oa 
or more heads or clusters, or an irregular panicle, either terminal or appa- 
rently below the top of the stem. Glumes several in each spikelet, imbri- 
cated all round the axis, all containing a perfect flower in their axil 
except sometimes the lowest one. Hypogynous bristles either 6 or fewer 
and shorter than the glume, or altogether wanting. 
A large genus, widely distributed over the whole world, and, like other 
large genera of Cyperacee, containing species very unlike each other in 
general habit. It has been repeatedly endeavoured to divide it into 
several, with characters derived from the hypogynous bristles, the shape 
of the base of the style, the number of its parts, etc., but the smaller groups 
so formed still include species as unlike each other as those of the original 
genus, whilst species closely resembling each other in every other respect 
have become widely separated. The genus is therefore here retained in 
its integrity, distinguished from Rhynchospora by the glumes all bearing 
flowers except the lowest, from Cyperus by the arrangement of the glumes, 
and from Blysmus by the arrangement of the spikelets. 
Spikelets solitary on each stem. 
Stems branched, leafy, floating in water or in matted tufts on 
its edge - y - ; ° . 7. &. fluitans. 
Stems simple, erect or ascending. 
Outer bract of the spikelet without any leafy tip. 
Stems very slender, not 3 inches high. Styles 3-cleft. 
Spikelet dark brown, scarcely more than 1 line long . 1. 8S. acieularis 
Spikelet pale- -coloured, usually 14 lines long or ‘rather 
more . . 2 &. parvulus. 
Stems rather stiff, 3 or 4 inches to a, foot high or more. 
Styles mostly Q-cleft . . - ; ° ; ; . 3&3. S. palustris. 
Styles mostly 3-cleft. 
Sheaths at the base of the stem obtuse or oblique at the 
top, without any leafy tip. Spikelets oblong. 
Flowers numerous in each spikelet, the thickened 
base of the style rather bulb-shaped . 4. S. multicaulis. 
Flowers 3 to 6 in each spikelet, the thickened pase 
of the style gradually tapering from the nut . 5. &. paucifiorus, 
Sheaths at the base of the stem with a short leafy tip. 
Spikelet ovoid. 6. S. ce@spitosus. 
Outer bract of the spikelet with a leafy tip as long as the spikelet 
or longer. 
Stems rather firm, 6 inches to a foot high, with numerous 
sheaths at the base, each with a short point . 6. S. cespitosus. 
wae very slender, 1 to 6 inches high, with 1 or 2 subulate 
eaves. 
Nut marked with longitudinal ribs and furrows ,. . 
Nut without ribs or furrows 
Spikelets 2 or more, in a cluster or umbel below the summit of 
the stem. 
Stems very slender, 1 to 6 inches high, with 1 or 2 subulate 
leaves. 
Nut marked with longitudinal ribs and furrows . . . 8. S. setaceus, 
Nut without ribs or furrows ; ; : ; ; a . 9. S&S. riparius. 
Stems firm, 1 to 2 f-et high or more. 
Stems leafless, or with 1 or 2 short, stiff leaves at the base. 
Stems acutely triangular from near the base. 
Spikelets all sessile, in a close cluster. Leaf-blade nar- 
row, 2 or 3 inches long . . 11. S&S. pungens, 
Spikelets more or less pedicellate, ina ‘compound cluster. 
Leat-blade very short . , 12. S&S. triqueter, 
Stems cylindrical, or scarcely angular at the top. 
Spikelets very small but very numerous, densely packed 
in one or more small, globular heads . . 10, 8. Holoschenus, 
Spikelets rather large, in a cluster or irregular umbel . 13. §, lacustris, 
. S. setaceus. 
. S. riparius, 
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