* Stem leafy and branching.
** Stem leafy and simple, or leafless. †Rootstock not bulbous. ‡ Flowers purplish.
(287) Simethis - perianth-leaves spreading, deciduous; filaments bearded; flowers panicled.
‡‡ Flowers yellow.
(289) Tofleldia - perianth-leaves persistent; flowers in short spikes.
‡‡ Bootstock bulbous.
(290) Allium - perianth-leaves rather spreading; flowers umbellate.
(291) Butomus - perianth coloured, resembling a corolla; stamens nine.
* Perianth-segments six, large, coloured, nearly equal.
** Perianth-segments three large coloured, and three small herbaceous.
(292) Alisma - flowers perfect; calycine and corolline segments three each; stamens six; carpels numerous, one-seeded.
(293) Actinocarpus - flowers perfect; calycine and corolline segments three each; stamens six; carpels 6-8, spreading in a radiant manner, two-seeded.
(294) Sagittaria - flowers monoecious; male flowers with numerous stamens; female flowers with numerous one-seeded compressed carpels upon a globose receptacle.
** Perianth-segments all small, and but slightly coloured.
(295) Triglochin - perianth of deciduous leaves; stamens six; carpels attached to an angular axis from which they at length separate at the base.
(296) Juncus - perianth glumaceous, six-leaved; capsules threecelled, three-valved.
(297) Luzula - as in Juncus, but the capsules one-celled, threevalved.
* Flowers unisexual, the stamens and ovaries within separate glumes.
(298) Carex - flowers in imbricated spikes, each covered by a glume; ovaries enclosed in bottle-shaped utricles formed of the persistent perigones.
** Flowers perfect, the stamens and ovaries within the same glume.
† Glumes or bracts distichous or two-ranked.
(299) Schcenus - spikelets 2-4-flowered; glumes 6-9, the lower ones smaller, empty.
†† Glumes or bracts regularly imbricated.
‡ Lower glumes empty or larger than the fertile ones, sometimes all fertile.
§ Bristles not so long as the glumes, or wanting.
(300) Blysmus - bristles 3-6; nut plano-convex, tipped with the base of the style, which is not dilated; spikelets in two-ranked spikes.
(301) Eleocharis - bristles 3-6;'nut compressed, crowned with the persistent dilated base of the style; spikelets solitary.
(302) Scirpus - bristles about six or none; nut plano-convex or trigonous, tipped with the filiform base of the style, which is not dilated; spikelets solitary clustered or panicled.
§§ Bristles at length much longer than the glumes.
(303) Eriophorum - bristles (in the fruiting state) silky; nut trigonous; spikelets solitary or umbellate.
‡‡ Lower glumes empty, or smaller than the fertile ones.
(304) Rhynchospora - bristles about six; nut compressed, convex on both sides, crowned with the dilated base of the style.