Genus 1, species 20. Tropical and South Africa. Some are used as ornamental plants, especially the lattice-leaf (A. fenestralis Hook. fil.) with perforated leaves. The tubers are edible and contain starch. (Including
Ouvirandra Thouars). Aponogeton Thunb.
[FAMILY 11.] SCHEUCHZERIACEAE
Marsh herbs. Leaves linear, with axillary scales. Flowers in terminal racemes or spikes, regular, hermaphrodite. Perianth of 6 segments, usually green. Stamens 3-6. Anthers turned outwards; pollen-grains ovoid. Ovary 3-6-celled. Ovule 1 in each cell, ascending, inverted. Stigmas sessile. Seeds exalbuminous, with a straight embryo. (JUNCAGINEAE, under NAIADACEAE.)
Genus 1, species 4. North, South, and West Africa. The leaves and fruits of some species are edible. (Juncago Tourn.) Triglochin L.
SUBORDER ALISMATINEAE
[FAMILY 12.] ALISMATACEAE
Aquatic or marsh herbs, with milky juice. Leaves with axillary scales. Flowers regular. Perianth of 3 sepals and 3 petals, rarely in the female flowers of 3 sepals only. Stamens 6 or more, rarely 3. Anthers opening outwards. Pollen-grains globular. Carpels 6 or more, rarely 3, distinct or united at the base. Ovules solitary in each carpel, rarely two or more, inverted. Seeds without albumen; embryo curved.—Genera 9, species 15. Tropical and North Africa. (Plate 6.)
1. Carpels on a large and distinctly convex receptacle. Inner perianth-segments petal-like, larger than, or almost as large as the outer. Stamens
6 or more. [Tribe SAGITTARIEAE.] 2
Carpels on a small and almost flat receptacle. 4
2. Flowers hermaphrodite. Ripe carpels numerous, slightly compressed, with many ribs.—Species 3. Central and North-west Africa. (Under
Alisma L.) Echinodorus Engelm.
Flowers unisexual or polygamous. Ripe carpels much compressed laterally. 3
3. Flowers monoecious or polygamous. Petals a little longer than the sepals.
Carpels many. Ripe carpels with two crest-like ribs.—Species 1.
Tropics. (Lophiocarpus Miq., under Sagittaria L.) Lophotocarpus Th. Dur.
Flowers dioecious. Petals shorter than the sepals, white. Carpels 7-9.
Ripe carpels with 3 ribs.—Species 1. German South-west Africa. Rautanenia Buchenau
4. Petals much smaller than the sepals or wanting. Stamens 3 or 9. [Tribe
WIESNEREAE.] 5
Petals larger than the sepals, coloured. Stamens 6, rarely 9. [Tribe
ALISMEAE.] 6
5. Flowers dioecious. Petals in the female flowers wanting. Stamens 9.
Carpels about 12.—Species 1. East Africa. Burnatia Mich.
Flowers monoecious. Petals present, but very small and falling off early.
Stamens 3. Carpels 3-6.—Species 2. East Africa and Madagascar.
(Wisneria Mich.) Wiesnera Mich.
6. Carpels 6-8, united at the base and spreading horizontally, containing
2 or more ovules each and opening by a lid when ripe.—Species 2. North
Africa. The root-stock is edible. Damasonium Tourn.
Carpels 6-20, distinct, with a single ovule in each, indehiscent. 7
7. Flowers polygamous-monoecious. Carpels 15-20. Pericarp bony within, hollow on either side. Leaves sagittate.—Species 3. Tropics. (Plate
6.) Limnophyton Miq.
Flowers hermaphrodite. Leaves ovate, cordate, or lanceolate. 8
8. Carpels 6-12, irregularly whorled, slightly compressed and 3-5-ribbed when ripe; pericarp woody within.—Species 2. Tropics and Egypt.
(Under Alisma L.) Caldesia Parl.
Carpels 15-20, distinctly whorled, much compressed and 2-ribbed when ripe; pericarp leathery or parchment-like.—Species 1. North and
East Africa. The root-stock contains starch and is used in medicine.
“Water-plantain.” Alisma L.
SUBORDER BUTOMINEAE
[FAMILY 13.] BUTOMACEAE