This section is from the book "British Wild Flowers - In Their Natural Haunts Vol5-6", by A. R. Horwood. Also available from Amazon: A British Wild Flowers In Their Natural Haunts.
Order 90. Eriocaulonaceae. - Herbaceous plants; leaves linear, with grass habit; flowers 1-sexual, small, in head, with involucre; perianth of 2-6 scales, 3 inner, 3 outer; stamens 2-6; anthers 2-celled; ovary 2-3-celled, superior; ovule I, pendulous; stigmas 2-3; fruit a capsule, 2-3-valved.
Glumacae (Glumifloroe in part)
Flowers in spikes, with glumes; perianth of scales or absent; ovary I-celled; ovule 1; styles 2-3; stigmas 2-3.
Order 91. Cyperaceae. - Plants herbaceous, with grass habit; stem 3-angled, solid; leaves in 3 ranks; sheaths entire; flowers 1-2-sexual, in axils of glumes of spikelets; perianth of hypogynous scales or 3-6 bristles; stamens 1-3; ovary I-locu-lar; style 1; stigmas 2-3; ovule 1; fruit a nut or achene.
Order 92. Graminaceae. - Plants herbaceous, grass-like; stem hollow between nodes; leaves in 2 rows; sheaths split; flowers 2-sexual as a rule, sessile, in spikelets; enclosed in glumes and paleae; perianth of scales or none; stamens 3; anthers versatile; ovary I-locular; stigmas 2, feathery; style none; ovule 1; fruit a caryopsis or false achene.