392 97. GRAMINEA. 
—y. angustifolia; spikelets small, 1. slender long, lower 1. invo- 
lute.-—Common. P. VI. VII. 
12. P. compressa (L.); panicle rather unilateral spreading 
when in flower otherwise close, spikelets ovate or oblong-ovate 
of 5—7 obtuse slightly webbed f1., outer pale with 3 hairy nerves, 
upper sheath about as long as its leaf, uppermost knot at about 
the middle of the stem, ligule short truncate.—E. B. 365. P. 37. 
—St. decumbent at the base, then erect, very much compressed, 
1—13 ft. high. Outer pale with no intermediate nerves.—f. P, 
subcompressa (Parn.); outer pale 5-nerved, intermediate nerves 
glabrous faint. P.90.—Dry situations. P. VII. 
13. P. polynoda(Parn.) ; panicle erect ovate-lanceolate, spike- 
lets ovate or ovate-lanceolate of 4 or 5 not webbed fl., outer pale 
with 5 nerves the dorsal and marginal hairy, upper sheath not 
longer than its leaf, uppermost knot above the middle of the stem, 
ligule prominent obtuse.—P. 91.—St. decumbent at the base, 
then erect, compressed, 1—1} ft. high; knots 7 or 8, the second 
at about the middle of the stem. lL. acute. Panicle with short 
branches. Lowest fl. not longer than the large glume.—f. den- 
ticulata (Parn.) ; midrib of outer pale not hairy but denticulated 
throughout, ligule shorter, often one convoluted hair at the base 
of the fl. P. 92.—Dry stony places. P. VI. VII. E. 8. 
36. Giycertia R. Br. 
1. G.aquatica(Sm.); panicle erect repeatedly branched spread- 
ing, rachis semiterete, branches scabrous, spikelets linear-oblong 
of 5—10 fl., outer pale obtuse, 1. smooth with slightly compressed 
sheaths.—E. B.1315. P.44.—Root creeping. St.3—6 feet high, 
smooth, slightly compressed. Sheaths very long. L. long, rough 
on the edges and keel. Ligule short. Panicle large. Branches 
angular, slender, branched. Outer pale with the central nerve 
extending to the summit.— Watery places. P. VII. 
2. G, fluitans (R. Br.); panicle secund slightly branched very 
long, branches nearly simple roughish, spikelets linear of 7—12 
adpressed lanceolate-oblong acute fl., outer pale nearly thrice as 
long as broad, sheaths compressed.—P. 95.—St. ascending root- 
ing below, or floating. Sheaths nearly smooth, attiated, pale 
green, acute. Ligule elongate. Panicle remarkably elongated, 
often nearly simple; branches without callosities, ascending, 
lowermost usually in pairs. Spikelets adpressed. Outer pale 
rather shorter than the inner, with a triangular central pomt. 
Anthers about five times as long as broad, purple, pale yellow when 
empty.—Stagnant water and wet places. P. VI.—IX. 
3. G. plicata (Fries); panicle compound, branches compound 
nearly smooth erect when in flower divaricate with fruit, spikelets 
