482 THE SEDGE FAMILY. [Scirput. 



arrangement of the glumes, and from Blysmut by the arrangement of 



the spikelets, 



Spikelets solitary on each stem. 

 Stems branched, leafy, floating !n water or In matted tufta on 



its edge ... 7. 5. Jluitant. 



Stems simple, erect or ascending. 

 Outer bract of the gpikelet without any leafy tip. 

 Stems very slender, not 3 inches high. Styles 3 cleft. 

 Spikelet dark brown, scarcely more than 1 line long . 1. S. acicularit. 

 Spikelet pale-coloured, usually 1J lines long or rather 



more 2. S. parvulus. 



Sterna rather stiff, 3 or 4 inches to a foot high or more. 



Styles mostly 2-cleft S. S. paluttri*. 



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. multtcaulit, 

 Flowers 8 to 6 in each spikelet, the thickened base 



of the style gradually tapering from the nut . 5. S. pauciftorus. 

 Sheaths at the base of the stem with a short leafy tip. 



Spikelet ovoid 6. S. ceespitosut. 



Outer bract of the spikelet with a leafy tip as long as the 



gpikelet or longer. 



Stems rather firm, 6 inches to a foot high, with numerous 



sheaths at the base, each with a short point . . 



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 9. riparius. 



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 furrowi . . . S. S. setaceus. 



Nut without ribs or furrows 9. S. riparius. 



Stems firm, 1 to 2 feet high or more. 

 Stems leafless, or with 1 or 2 short, ttiff leaves at the base. 

 Stems acutely triangular from near the base. 

 Spikelets all sessile, in a close cluster. Leaf-blade nar- 

 row, 2 or 8 inches long 11. S. pungent. 



SpIkeleU more or less pedicellate, in a compound clus- 

 ter. Leaf-blade very short 12. 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. S. noloschomus. 

 Spikelets rather large, in a cluster or irregular umbel . 13. S. lacustris. 

 Stems bearing several long uaves. 



Spikelets large, brown, in a sessile cluster or close com- 

 pound umbel 14. S. martiimus. 



Spikelets small, green, very numerous, In a large, loose, 



compound panicle . .... 15. S. tylvaticus. 



1. S. acicularis, Linn. (fig. 1092). Needle A little slender tufted 

 plant, with the appearance of an annual, but emitting thread-like, 

 Creeping rootstocks ; the fine subulate stems scarcely 2 inches high, 

 with short sheaths at their base, and most of them bearing a single 

 terminal oblong spikelet, not 2 lines long, of a dark-brown colour, the 

 outer bract similar to the glumes. Flowers usually 6 to 8 in the spikelet. 

 Hypogynous bristles 3 or 4. Styles 3-cleft. Not obovoid, slightly 

 triangular. Eleocha,rii acicularis, Br. 



In wet, sandy places, the margin of lakes, Ac., widely spread over 



