KEY TO THE GENERA

FAMILY 1. CYCADACEAE

Stem simple, rarely branched at the top, woody, with mucilagineous juice. Leaves pinnate or pinnatisect, forming a tuft at the top of the stem and intermingled with scales. Flowers solitary, terminal, in the shape of a cone (but sometimes overtopped by the continued growth of the stem), dioecious, without a perianth. Stamens bearing many pollen-sacs on their lower side. Ovules 2-8 to each carpel, straight, with a single coat. Seeds drupe-like, albuminous. Embryo with two more or less united cotyledons.—Genera 3, species 25. Tropical and South Africa. (Plate 1.)

1. Stem growing through the female flower, covered with the remains of the old leaves. Leaf-segments one-nerved, coiled in bud. Carpels pinnately toothed or cleft, each with 4-8 ascending ovules.—Species 2, one growing wild in Madagascar and the neighbouring islands, the other cultivated and sometimes naturalized in various parts of Africa. Used as ornamental and medicinal plants; the fruits are edible and the pith contains starch (sago). [Tribe CYCADEAE.]  Cycas L.

Stem not growing through the female flower. Leaf-segments with several nerves, straight in bud. Carpels each with 2 descending ovules. [Tribe
ZAMIEAE.]  2

2. Leaf-segments with pinnate nerves. Stem without remains of old leaves at the base. Cone-scales (stamens and carpels) imbricate.—Species 2.
South-east Africa (Natal). Used as ornamental plants.  Stangeria Th. Moore

Leaf-segments with parallel nerves. Stem covered with the remains of old leaves. Cone-scales not imbricate.—Species 20. South and Central
Africa. The pith (Kaffir-bread) and the seeds of some species are eaten and also used for making a sort of beer. Several species yield gum or serve as ornamental plants. (Plate 1.)  Encephalartos Lehm.

CLASS II. CONIFERAE

FAMILY 2. TAXACEAE

Stem branched, woody, with resinous juice. Leaves alternate, linear or linear-lanceolate. Flowers solitary or the male umbellate, dioecious, without a perianth. Stamens with 2-9 pollen-sacs. Carpels free, one-ovuled, shorter than the seeds, sometimes rudimentary. Seeds 1-2, drupe-like, surrounded by a fleshy aril. Embryo with 2 or more free cotyledons.—Genera 2, species 9. (Under CONIFERAE.)

Stamens with 2 pollen-sacs and a triangular blade. Pollen-grains with air-bladders. Carpels distinctly developed. Ovule inverted, with two coats. Aril enveloping the seed. Leaves with resin-ducts.—Species
8. South and East Africa, Madagascar, Island of St. Thomas. They yield timber and bark for tanning. (Including Nageia Gaertn.) [Subfamily
PODOCARPOIDEAE.]  Podocarpus L’ Hér.

Stamens with 5-9 pollen-sacs and a peltate blade. Pollen-grains without air-bladders. Carpels rudimentary. Ovule straight, with one coat.
Aril cup-shaped. Leaves without resin-ducts.—Species 1. North-west
Africa. A poisonous, medicinal and ornamental plant, with hard wood.
“Yew.” [Subfamily TAXOIDEAE].  Taxus L.

FAMILY 3. PINACEAE

Stem branched, woody, with resinous juice. Leaves needle-or scale-like. Flowers unisexual, without a perianth. Stamens in catkins, with 2-5 pollen-sacs below the scale-like limb. Carpels arranged in the shape of a cone or bud, leathery woody or fleshy, when ripe. Ovules 2 or more to each carpel, rarely only 1. Seeds hidden by the carpels, without an aril. Embryo with 2 or more free cotyledons.—Genera 6, species 25. (Under CONIFERAE.) (Plate 2.)

1. Leaves alternate (as are also the floral leaves), but sometimes fascicled, needle-like. Stamens with 2 pollen-sacs. Pollen-grains with air-bladders.
Carpels divided into an inner and an outer scale, leathery or woody when ripe. Ovules and seeds 2 to each carpel; ovules turned downwards. [Tribe ABIETINEAE.]  2

Leaves opposite or whorled. Stamens with 3-5, very rarely 2 pollen-sacs.
Pollen-grains without air-bladders. Ovules turned upwards.
[Tribe CUPRESSINEAE.]  4

2. Shoots all alike (all long). Leaves solitary, flat. Pollen-sacs opening obliquely or transversely; connective without an appendage. Cones ripening the first year; scales leathery.—Species 2. North-west
Africa. The wood and the resin are used, the latter especially for the preparation of turpentine. “Silver fir.”  Abies Juss.

Shoots of two kinds, long and short. Leaves of the short shoots in clusters of two or more, surrounded by scales when young. Pollen-sacs opening longitudinally; connective with an appendage. Cones ripening the second or third year; scales woody.  3

3. Leaves all needle-like; those of the short shoots in clusters of many; those of the long shoots scattered. Flowers inserted upon short shoots, the males solitary. Cone-scales flat, imbricate, without a terminal appendage, deciduous.—Species 2. North-west Africa. They yield timber and medicinal drugs. “Cedar.”  Cedrus Loud.

Leaves of the short shoots needle-like, in clusters of two or three, very rarely solitary; leaves of the long shoots scale-like. Male flowers in spikes replacing short shoots; female flowers towards the end of the branches, replacing long shoots. Cone-scales thick, with a terminal umbonate appendage, persistent.—Species 4. North Africa; also naturalized in South Africa and St. Helena. Wood, bark, and resin are used for carpenters’ and joiners’ work, for tanning and for the manufacture of paper, tar, pitch, colophony, turpentine, and other chemical products, as well as in medicine. The seeds of some species (especially those of the stone-pine, P. Pinea L.) are edible. “Pine.”  Pinus L.

4. Fruit fleshy, berry- or drupe-like. Seeds not winged, as many as the carpels or fewer. Leaves usually needle-like.—Species 9. North and East
Africa. They yield wood, bark for tanning, resin, an essential oil, brandy (gin), and medicines; some are used as ornamental plants.
(Including Arceuthos Ant. & Kotschy and Sabina Spach).  Juniperus L.

Fruit woody, cone-like. Seeds winged, as many as the carpels or more.
Leaves usually scale-like.  5

5. Carpels 4, valve-like, separating at the apex when ripe, 1-10-seeded.—Species
8, one of them only naturalized. North, South, and southern
East Africa, Madagascar and Mauritius. Some of them (especially
C. quadrivalvis Vent.) yield timber and resin (sandarac) which is used for the preparation of lacquer, varnish, cement, and in medicine. (Including
Tetraclinis Mast. and Widdringtonia Endl.) (Plate 2.)  Callitris Vent.

Carpels 8-10, peltate, separating at the margins when ripe, many-seeded.—Species
1. Cultivated in North Africa as an ornamental plant and sometimes naturalized. It yields timber and is used in medicine.
“Cypress.”  Cupressus L.

CLASS III. GNETALES

FAMILY 4. GNETACEAE

Stem woody. Juice not resinous. Leaves opposite, undivided. Flowers in spikes or panicles or the female solitary, unisexual, but the male sometimes with rudimentary ovules. Perianth of the male flowers tubular or 2-4-parted, of the female bladder-like. Stamens 2-8. Ovule 1, erect, straight. Embryo with 2 cotyledons.—Genera 3 species 8. North and Central Africa.

1. Stem turnip-shaped, very short. Leaves 2, very large, sessile, linear, with
parallel nerves. Flowers in panicled spikes; the male consisting of
a 4-partite perianth, 6 stamens with 3-celled anthers, and a rudimentary ovule. Ovule with a single coat.—Species 1; German South-west
Africa and Angola. (Tumboa Welw.) [Subfamily WELWITSCHIOIDEAE.]  Welwitschia Hook. fil.

Stem shrubby or twining. Leaves numerous, not very large. Male flowers consisting of a 2-partite or a tubular, undivided perianth and
2-8 stamens with 1-2-celled anthers, without rudimentary ovules, but sometimes accompanied by sterile female flowers.  2

2. Leaves large, with a short foot-stalk, lanceolate oblong elliptical or oval, penninerved. Stem climbing. Flowers in spikes or panicles, the male consisting of a tubular, undivided perianth and 2 stamens with 1-celled anthers. Ovule with two coats.—Species 2. West Africa. The young leaves are used as a vegetable. [Subfamily GNETOIDEAE.]  Gnetum L.

Leaves scale-like. Male flowers in spikes or panicles, female solitary or in pairs. Male flowers consisting of a 2-partite perianth and 2-8 stamens with 2-celled anthers. Ovule with a single coat exceeding the perianth.—Species 5. North Africa and northern Central Africa.
The fruits of some species are eaten or used in medicine. [Subfamily
EPHEDROIDEAE.]  Ephedra L.

SUBDIVISION ANGIOSPERMAE

CLASS IV. MONOCOTYLEDONEAE

FAMILY 5. TYPHACEAE

Aquatic or marsh herbs with a creeping root-stock and simple stems. Leaves in two ranks, linear. Inflorescences spadix-like, cylindrical, superposed, interrupted by bracts, the lower female, the upper male. Flowers unisexual, without a perianth, but usually surrounded by hairs. Stamens 2-7; connective thickened; anthers opening lengthwise by two slits. Ovary 1-celled. Ovule 1, pendulous, inverted. Style and stigma simple. Fruit tardily dehiscent. Seed with abundant albumen and a long, axile embryo.

Genus 1, species 4. They are used as ornamental plants and in medicine, and yield potash and also materials for plaiting and stuffing and for the manufacture of paper and felt. The root-stock and the pollen are edible. “Reedmace.”  Typha Tourn.

FAMILY 6. PANDANACEAE

Shrubs or trees, usually with aerial roots. Leaves in three ranks, sword-shaped, usually spiny. Flowers dioecious, without bracts, arranged in solitary or panicled, spike-or head-like spadices, which are inserted in the axil of spathe-like bracts. Perianth none. Ovaries connate, 1-celled. Ovule 1, descending, inverted. Stigma 1, sessile. Fruits drupe-like, congested into a globose or ovoid head. Seed with abundant albumen. (Plate 3.)

Genus 1, species 65. Tropics. They yield timber, fibres, flowers used in perfumery, edible fruits, and medicinal drugs. “Screw-pine.”  Pandanus L.

FAMILY 7. SPARGANIACEAE

Aquatic or marsh herbs with a creeping root-stock. Leaves in two ranks, linear. Flowers unisexual, in globular heads, the lower of which are female. Perianth of membranous scales. Stamens 3 or more. Ovary superior, 1-2-celled. Ovule 1 in each cell, pendulous, inverted. Style simple, stigmas 1-2. Fruits drupe-like. Seed with a mealy albumen and a large, axile embryo. (Under TYPHACEAE.)

Genus 1, species 2. North-west Africa. “Bur-reed.”  Sparganium L.

ORDER HELOBIAE

SUBORDER POTAMOGETONINEAE

FAMILY 8. POTAMOGETONACEAE

Aquatic herbs. Leaves with axillary scales. Flowers solitary or spicate, regular, with 1-4-merous whorls. Perianth simple and little developed or wanting. Stamens 1-4. Anthers sessile, opening outwards or laterally. Carpel 1, with a 1-celled ovary, or several distinct or almost distinct carpels. Ovules solitary in each carpel, very rarely 2, pendulous or laterally fixed Fruit indehiscent. Seed exalbuminous. Embryo with a strongly developed radicle.—Genera 8, species 35. (Including ZOSTERACEAE, under NAIADACEAE.) (Plate 4.)

1. Flowers in spikes, hermaphrodite or polygamous, without a perianth, but the stamens sometimes provided with a sepal-like connective.  2

Flowers solitary or in cymes, unisexual.  5

2. Spikes with a flat axis, at the time of flowering enclosed in the sheaths of the uppermost leaves. Stamen 1. Pollen-grains filiform. Carpel
1. Stigmas 2, on a short style. Embryo with a very large radicle and a tail-like cotyledon. Submerged marine plants.—Species 2. North and
South Africa and Madagascar. Used for stuffing and as packing material.
“Grass-wrack.” [Tribe ZOSTEREAE.]  Zostera L.

Spikes with a cylindrical axis, at the time of flowering not enclosed in the sheaths of the uppermost leaves. Stamens 2-4. Stigma 1, undivided
or many-parted.  3

3. Spikes compound, submerged. Spikelets shorter than their bracts. Flowers polygamous. Stamens 3, rarely 4. Pollen-grains filiform. Carpel 1.
Stigma divided (or provided with narrow appendages). Embryo with
a very large radicle and a straight cotyledon resembling the leaves of the plumule. Marine plants.—Species 1. Mediterranean Sea. The leaves are used for packing and thatching, and also in medicine. [Tribe
POSIDONIEAE.]  Posidonia Koen.

Spikes simple, above the water. Flowers hermaphrodite. Pollen-grains globular or bent. Carpels usually 4. Stigma simple, more or less peltate. Embryo with a curved cotyledon. [Tribe POTAMOGETONEAE.]  4

4. Spikes two-flowered. Stamens 2. Anthers with a very short appendage and kidney-shaped cells opening outwards. Pollen-grains bent. Fruit stalked. Embryo with a very thick radicle. Salt-water plants. Leaves subulate.—Species 1.  Ruppia L.

Spikes several-flowered. Stamens 4. Anthers with a sepal-like appendage and straight cells opening laterally. Pollen-grains globular. Fruit sessile. Embryo with a slightly thickened radicle.—Species 20. Used for manure; some have edible root-stocks. “Pondweed.” (Plate 4.)  Potamogeton Tourn.

5. Perianth none. Stamens 2. Pollen-grains filiform. Carpels 2. Stigmas strap-shaped, longer than the style. Embryo with an accumbent cotyledon. Marine plants. [Tribe CYMODOCEAE.]  6

Perianth present, at least in the female flowers. Stamens 1-2. Pollen-grains globular. Carpels 3-9. Stigma shield- or funnel-shaped, shorter than the style. Embryo with a hooked or rolled cotyledon.
Fresh- or brackish-water plants. [Tribe ZANICHELLIEAE.]  7

6. Stigma 1. Anthers inserted at slightly different heights. Ripe carpels scarcely compressed.—Species 2. Indian Ocean, Red Sea, Angola.
(Halodule Endl., under Cymodocea Koen.)  Diplanthera Thouars

Stigmas 2. Anthers inserted at the same height. Ripe carpels compressed and keeled.—Species 5. North Africa, Senegambia, East Africa,
Madagascar and neighbouring islands. (Including Phycagrostis Ascherson)  Cymodocea Koen.

7. Perianth in the male flowers none, in the female cup-shaped and undivided.
Anthers stalked, opening by 2 longitudinal slits. Carpels usually 4, slightly curved, with a peltate stigma.—Species 1. North and South
Africa, southern West Africa, Madagascar and neighbouring islands.  Zannichellia Mich.

Perianth in the male flowers 3-toothed, in the female consisting of 1-3 segments. Anthers sessile, opening with one longitudinal slit. Carpels
3, straight, with a funnel-shaped stigma.—Species 1. North-west
Africa (Algeria).  Althenia Fr. Petit

FAMILY 9. NAIADACEAE

Herbs growing in fresh or brackish water. Leaves linear, toothed or spiny. Flowers axillary, solitary or in glomerules, unisexual. Perianth little developed, in the male flowers simple or double, sack-like, in the female simple and sack-like or wanting. Stamen 1. Anthers 1-or 4-celled. Pollen-grains globular or ovoid. Ovary 1-celled. Ovule 1, erect, inverted. Style 1; stigmas 2-3. Seed with a hard coat, exalbuminous. Embryo straight, with a large radicle and a well developed plumule.

Genus 1, species 10. (Including Caulinia A. Braun)  Naias L.

FAMILY 10. APONOGETONACEAE

Aquatic herbs with a tuberous root-stock. Leaves radical, narrow, with several longitudinal and many transverse nerves. Flowers in 1-4 spikes connected at the base, enclosed when young in a sheath, and rising above the water. Perianth of 1-3 more or less brightly coloured segments. Stamens 6 or more, hypogynous, free. Anthers attached by the base, opening with two longitudinal slits. Carpels 3-8, distinct. Ovules in each carpel 2-8, basal or sutural, ascending, inverted. Fruits membranous, dehiscent. Seeds 2 or more, erect, exalbuminous, with a straight embryo. (Under NAIADACEAE.) (Plate 5.)

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

Aquatic or marsh herbs. Leaves linear or lanceolate. Flowers in umbel-like cymes, regular, hermaphrodite. Perianth of 6 segments, all, or the inner ones only, petal-like. Stamens 9, very rarely fewer. Pollen-grains globular. Carpels 6, very rarely fewer, distinct or united at the base only, opening when ripe along the ventral suture. Ovules on irregularly branched parietal placentas, numerous, inverted. Seeds without albumen.—Genera 2, species 2. North and Central Africa. (Under ALISMACEAE.)

Perianth-segments nearly equal, all petal-like, pink, persistent. Embryo straight. Leaves linear. Juice not milky.—Species 1. North-west
Africa (Algeria). Used as a garden plant. The root-stock is edible.
“Flowering-rush.”  Butomus Tourn.

Perianth-segments unequal, outer sepal-like, inner petal-like, white, falling off very early. Embryo horseshoe-shaped. Leaves elliptical. Juice milky.—Species 1. Northern part of Central Africa. (Butomopsis
Kunth)  Tenagocharis Hochst.

FAMILY 14. HYDROCHARITACEAE

Aquatic herbs. Leaves with axillary scales. Flowers enclosed when young in a one-or several-flowered spathe of one or two bracts, regular, rarely somewhat irregular. Perianth consisting of a calyx and a corolla, rarely simple. Stamens 2-12. Anthers opening outwards or laterally. Ovary inferior, more or less distinctly one-celled, with 2-15 parietal placentas, which sometimes form incomplete dissepiments. Seeds without albumen.—Genera 10, species 40. (Plate 7.)

1. Stigmas 2-5. Placentas as many, slightly raised.  2

Stigmas 6 or more. Placentas as many, much projecting and generally meeting in the centre of the ovary.  6

2. Petals none. Stamens 3. Pollen-grains filiform. Stigmas several times as long as the sepals. Embryo with a strongly developed radicle.
Totally submerged marine plants. Leaves more or less distinctly stalked.—Species 2. Indian Ocean. [Subfamily HALOPHILOIDEAE.]  Halophila Thouars

Petals present, but sometimes very small and falling off very early. Pollen-grains globular. Stigmas at most twice as long as the sepals. Embryo with a not very strongly developed radicle. Freshwater plants; flowers raised above the water. Leaves sessile. [Subfamily VALLISNERIOIDEAE.]  3

3. Leaves whorled. Spathes 1-flowered. Flowers unisexual. Stamens 3.—Species
1. Upper Nile, Madagascar, Mauritius. Used in refining sugar. [Tribe HYDRILLEAE.]  Hydrilla L. C. Rich.

Leaves spirally arranged. Spathes of the male flowers several-flowered.  4

4. Spathes of the male flowers 2-10-flowered, not breaking away from the stem. Stamens 3-9. Ovules inverted.—Species 3. Madagascar and
Angola. [Tribe BLYXEAE.]  Blyxa Noronha

Spathes of the male flowers many-flowered, breaking away from the stem.
Stamens 2-3. Ovules straight. [Tribe VALLISNERIEAE.]  5

5. Male flowers regular, with 3 fertile and 2-4 sterile stamens. Stigmas linear, 2-cleft or 2-parted. Leaves one-nerved. Stem elongated.—Species
10. Tropical and South Africa.  Lagarosiphon Harv.

Male flowers somewhat irregular, with 2-3 fertile stamens and sometimes
a sterile one. Stigmas ovate, notched or two-toothed. Leaves several-nerved.—Species
2. North and Central Africa. Used in refining sugar.  Vallisneria Mich.

6. Leaves in two rows. Ovules inverted, inserted in the angles formed by the placentas and the wall of the ovary. Radicle of the embryo strongly developed. Marine plants. [Subfamily THALASSIOIDEAE.]  7

Leaves in rosettes. Ovules inverted, but inserted on the whole surface of the placentas, or straight. Radicle of the embryo not strongly developed. Freshwater plants. [Subfamily STRATIOTOIDEAE.]  8

7. Scape of the male flowers short, of the female long and at length spirally twisted. Male spathes several-flowered; flowers with 3 petals and 3 stamens.—Species 1. Madagascar and Red Sea. Yields fibres and edible seeds.  Enalus L. C. Rich.

Scapes moderately long, not spirally twisted. Male spathes one-flowered; flowers without petals, with 6 stamens.—Species 1. East Africa.  Thalassia Soland.

8. Placentas undivided. Ovules straight. Fertile stamens 9. Stem emitting runners. Leaves floating.—Species 1. Algeria and Madagascar.
“Frogbit.” [Tribe HYDROCHARITEAE.]  Hydrocharis L.

Placentas two-cleft. Ovules inverted. Seeds very numerous. Fertile stamens 6-12. Stem very short, without runners. Leaves at least partially submerged. [Tribe OTTELIEAE.]  9

9. Flowers hermaphrodite. Spathes one-flowered. Stigmas 6.—Species 9.
Tropics and Egypt. Some are used as vegetables. (Plate 7.)  Ottelia Pers.

Flowers dioecious. Spathes of the male flowers several-flowered. Stigmas
9-15.—Species 10. Tropics. Some are used as vegetables.  Boottia Wall.

ORDER TRIURIDALES

FAMILY 15. TRIURIDACEAE

Small, pale, yellowish or reddish herbs. Leaves reduced to scales. Flowers in racemes, regular, monoecious. Perianth of 6 petaloid, valvate segments united at the base. Stamens 3; filaments short or wanting; anthers 2-celled, opening transversely. Carpels inserted on a convex or conical receptacle,

numerous, distinct; styles lateral; ovules solitary, erect, inverted. Fruits dehiscing by a longitudinal slit.

Genus 1, species 3. West Africa and Seychelles. (Including Seychellaria
Hemsl.)  Sciaphila Blume

ORDER GLUMIFLORAE

FAMILY 16. GRAMINEAE

Stem usually herbaceous and hollow between the nodes. Leaves alternate, usually linear and furnished at their base with a sheath split open on one side and ending in a ligule. Inflorescence consisting of spikelets, rarely of single flowers, usually enclosed by 2 glumes (outer or empty glumes) and arranged in spikes, racemes, or panicles. Flowers in the axil of the flowering glume (or valve), subtended by the usually 2-keeled palea and sometimes by one or two, rarely more, minute lodicules. Perianth none. Stamens 1-6, usually 3. Anthers opening by 2 slits or pores. Ovary 1-celled. Ovule 1, erect or laterally affixed, slightly curved, with the micropyle turned downwards. Styles 2, rarely 3 or 1. Fruit indehiscent; pericarp usually dry and adnate to the seed. Embryo outside the copious albumen.—Genera 205, species 1600. “Grasses.” (Plate 8.)