496 THE SEDGE FAMILY. (Carew. 
Asia, from the Mediterranean to the Arctic regions, and in North 
America. Fl. spring and summer, The principal forms occurring in 
Britain, often considered as species, are :— 
a. C. rigida,Good. A dwarf alpine form, scarcely 6 inches high, with 
short, flat, and rigid leaves. In exposed situations, at great elevations, 
or at high northern latitudes. 
b. C. cespitosa, Sm. (vulgaris, Fries., Goodenovii, Gay). Usually 1 to 3 
feet high, loosely tufted, with narrow leaves, including many inter- 
mediate forms passing oradually into the preceding and following 
varieties. Abundant throughout Britain. 
c. C. stricta, Good. Usually about 2 feet high, more glaucous and ~- 
tufted than the last variety, with narrow leaves, rather long spikelets, 
the fruits more distinctly arranged in 8 or 9 rows, and their nerves 
more strongly marked. Equally common with the last variety, but 
usually in more open situations, 
d. C. aquatilis, Wahl, A very tall, leafy form, with slender spikelets, 
approaching C. acuta. In bogs and marshes in Scotland, rare. 
[e. C. trinervis, Degl. A short, stout plant, with narrow rigid leaves, the 
margins of which are involute. Confined to the shores of N.W. Europe, 
and recently found in wet, sandy places on the Norfolk coast. ] 
20. C. acuta, Linn. (fig. 1130). Acute C.—This may again be a mere 
luxuriant variety of C. cespitosa. It attains 2 or 3 feet, with long, 
flaccid leaves, and leafy bracts ; the female spikelets are often 3 inches 
long or more; the glumes all narrow and acute, and the fruits them- 
selves narrower than in most varieties of C. ccspitosa. 
In wet meadows, and marshes, generally distributed over the area of 
C. cespitosa, and not uncommon in Britain. Fl, spring and early 
summer. - 
21. C. alpina, Sw. (fig. 1131). Alpine C.—A rather slender species, 
5 inches to a foot high, tufted or shortly creeping, with short leaves. 
Spikelets about 3, ovoid, black or dark brown; the terminal one mixed, 
hairy, a few male flowers at its base; the 2 others female, one close to 
the terminal one, the other a little lower down, on a short stalk, in the 
axil of a leafy bract. Styles 3-cleft. Fruit green, obtusely triangular, 
shortly beaked, and projecting beyond the glume. C. Vahli, Schk. 
On mountain-rocks, in northern Europe and Asia. In Britain only 
in two localities on the Clova mountains of Scotland. Fl. summer. 
22. C. Buxbaumii, Wabhlenb. (fig. 1132). Buaxbaum’s C.—Rootstock 
shortly creeping, but the stems often densely tufted, 1 to 2 feet high, 
with rather long leaves. Spikelets usually 3, in a loose spike, the 
terminal one male at the base, the others all female and sessile, or the 
lowest on a very short stalk. Lowest bract, and sometimes the next 
also, leafy. Glumes dark brown, mostly pointed. Styles 3-cleft. 
Fruits of a pale colour, much resembling those of C. cespitosa, usually 
as long as or longer than the glumes, rather obtusely angled, and not 
beaked. 
In bogs, in northern and Arctic Europe, Asia, and North America, 
in the mountains of central Europe, and in Australia, In British Islands — 
only known from Lough Neagh, in Ireland. fl. July. é 
23. C. atrata, Linn. (fig. 1133). Black C. ~ Stans loosely tufted, 
3 to 14 feet high; the leaves broad and flaccid, with loose sheaths. 
Spikelets 3 or 4, black or dark brown, cylindrical, 8 or 9 lines long ; 
