The flowering plants of Africa / An analytical key to the genera of African phanerograms

by Franz Thonner

Shrubs or trees. Leaves alternate, undivided, stipulate. Inflorescence cymose. Sepals 4-5, imbricate in bud. Petals 4-5, usually 2-cleft. Disc present, but sometimes reduced to separate glands. Stamens 5, sometimes only 2-3 fertile. Anthers opening inwards. Ovary 2-3-celled, usually superior. Ovules 2 in each cell, pendulous, inverted; raphe ventral. Style 2-3-cleft or undivided with 2-3 stigmas. Fruit a nut or drupe. Seeds 1-2, exalbuminous.—Genera 2, species 75. Tropical and South Africa. (CHAILLETIACEAE.) (Plate 79.)

Petals unequal, united below into a long tube, 2-cleft, imbricate in bud.
Sepals united below, unequal. Fertile stamens 2-3. Disc semi-annular.—Species
2. Central Africa. Tapura Aubl.
Petals equal, free or united at the base, rarely higher. Fertile stamens
5.—Species 75. Tropical and South Africa. Some are poisonous.
(Chailletia DC.) (Plate 79.). Dichapetalum Thouars

SUBORDER TRICOCCAE

[FAMILY 122.] EUPHORBIACEAE

Flowers unisexual. Stamens hypogynous, rarely (Bridelia) perigynous. Anthers 2-celled. Ovary superior or naked, usually 3-celled. Ovules solitary in each cell, or 2 side by side, pendulous, inverted; raphe ventral; micropyle usually covered by an outgrowth of the placenta. Fruit generally separating into 3 dehiscing mericarps. Seeds usually albuminous; embryo axile, radicle superior.—Genera 122, species 1200. (Including DAPHNIPHYLLACEAE.) (Plate 80.)

1. Ovule 1 in each ovary-cell. [Subfamily CROTONOIDEAE.]. 2
Ovules 2 in each ovary-cell. Juice not milky. [Subfamily PHYLLANTHOIDEAE.]. 76
2. Inflorescence consisting of partial inflorescences having the appearance of a single flower and containing one female flower and several or many male ones surrounded by a lobed involucre with glandular appendages.
Petals none. Stamen 1. Ovary 3-4-celled. Juice milky. [Tribe
EUPHORBIEAE.]. 3
Inflorescence not consisting of partial inflorescences looking like a single
flower. 11
3. Male flowers with a cupular, entire or 3-6-lobed perianth. Female flowers with a 3-4-toothed or -cleft perianth. Trees or shrubs. 4
Male flowers without a perianth. 5
4. Involucre of the partial inflorescences split at one side and consisting of 4 or more bracts. Ovary 3-celled. Style 3- or 6-cleft. Trees.—Species
3. Tropics. Poisonous and used medicinally. Anthostema Juss.
Involucre closed all round and consisting of 4 bracts. Ovary 4-celled.
Style 4-parted.—Species 3. Equatorial West Africa. Dichostemma Pierre
5. Involucre of the partial inflorescences with unequal lobes and with an appendage, in the axil of which the glands are inserted. Shrubs.—Species
2. Madagascar. Pedilanthus Neck.
Involucre with equal lobes, but sometimes surrounded by a one-sided gland. 6
6. Involucre irregular, with a single gland sometimes embracing the partial inflorescence and split at one side only. 7
Involucre regular, with several glands sometimes united into a ring or cup. 9
7. Involucre with a narrow gland not enveloping the partial inflorescence.
Female flowers with a perianth. Bracts subtending the involucres united high up. Spiny shrubs.—Species 1. East Africa. Stenadenium Pax
Involucre with a broad gland enveloping the partial inflorescence. Herbs. 8
8. Female flowers with a perianth. Bracts subtending the involucres united at the base.—Species 2. East Africa. (Under Monadenium Pax). Lortia Rendle
Female flowers without a perianth. Bracts subtending the involucres united high up.—Species 10. Central Africa. Monadenium Pax
9. Glands of the involucre united into a ring or cup.—Species 10. Tropical and South-east Africa. Some are poisonous. Synadenium Boiss.
Glands of the involucre separate. 10
10. Fruit a drupe.—Species 1. West Africa. (Under Euphorbia L.) Elaeophorbia Stapf
Fruit a capsule.—Species 320. Many of them are poisonous, some yield timber, gum, rubber, oil, and medicaments, or serve as garden- or hedge-plants. “Spurge.” Euphorbia L.
11. (2.) Filaments bent inwards in the bud. Calyx 4-6-partite, imbricate or subvalvate in bud. Corolla present, at least in the male flowers.
Inflorescence spike- or raceme-like. Leaves and young shoots clothed with scales or stellate hairs.—Species 100. Tropical and South Africa.
Several species are poisonous, some yield gum-lac, incense-wood, oil, and medicaments, or serve as ornamental plants. [Tribe CROTONEAE.] Croton L.
Filaments straight in the bud. 12
12. Calyx of the male flowers with valvate or closed aestivation. [Especially tribe ACALYPHEAE.] 13
Calyx of the male flowers with imbricate or open aestivation. 59
13. Corolla present in the male flowers. 14
Corolla absent in the male flowers. 24
14. Petals of the male flowers more or less united. Rudimentary pistil cup-shaped or wanting. Style-branches 2. Flowers dioecious. Hairy undershrubs, shrubs, or trees. 15
Petals of the male flowers free from each other, but sometimes (Caperonia) adnate to the staminal tube; in this case rudimentary pistil club-shaped and style with many branches. 17
15. Petals united high up. Calyx bursting irregularly. Disc of 5 glands alternating with the petals. Stamens 12-20. Rudimentary pistil absent. Climbing shrubs with reddish-brown hairs. Leaves 3-7-nerved.
Flowers in panicles.—Species 5. West Africa. Fibre-yielding plants. Manniophyton Muell. Arg.
Petals united at the base only. Calyx 4-5-parted. Stamens 4-5.
Undershrubs or trees. 16
16. Flowers 4-merous. Anthers turned inwards. Disc within the stamens.
Trees. Leaves 3-nerved. Young shoots with rusty-brown hairs.
Flowers in panicles.—Species 1. West Africa (Cameroons). Schubea Pax
Flowers 5-merous. Anthers turned outwards. Glands alternating with the stamens; a cupular disc also present within them. Undershrubs.
Young shoots with white hairs. Flowers in axillary clusters.—Species
1. East Africa (Somaliland). Gilgia Pax
17. Style many-cleft. Rudimentary pistil of the male flowers club-shaped.
Stamens 5-10, united below. Petals adnate to the staminal tube.
Disc indistinct. Flowers in racemes. Herbs or undershrubs, usually hispid.—Species 9. Tropics. Several species yield fibre. Caperonia St. Hil.
Style 2-4-cleft. Rudimentary pistil of the male flowers 2-3-cleft or wanting. 18
18. Stem herbaceous or woody at the base only, hairy or cottony. Flowers in racemes, monoecious. Male flowers without a disc.—Species 7. Northern and tropical Africa. Some are poisonous or yield dyes and medicaments.
“Turnsole.” (Tournesolia Scop.) Chrozophora Neck.
Stem woody. Male flowers usually with a disc reduced to separate glands. 19
19. Young branches and leaves clothed with scales. Inflorescence spicate or racemose. Flowers dioecious. Stamens 15-20.—Species 12. West
Africa. Crotonogyne Muell. Arg.
Young branches and leaves glabrous, downy, or clothed with star-like hairs. Inflorescence spicate, racemose, or paniculate; in the two
former cases stamens 6-14. 20
20. Young branches and leaves clothed with 2-cleft or star-like hairs. Trees.
Leaves palmately nerved. Flowers in panicles, monoecious. Stamens
8-20. Fruit a drupe.—Species 2. Cultivated and naturalized in the tropics. They yield timber, gum-lac, tanning bark, dye-stuffs, and edible oily seeds (“candle-nuts”). Aleurites Forst.
Young branches and leaves clothed with simple hairs, or glabrous. Shrubs.
Inflorescence spicate or racemose, more rarely paniculate, but then leaves pinnately nerved. Fruit a capsule. 21
21. Flowers in panicles, dioecious. Calyx 2-3-partite in the male flowers,
4-partite in the female. Corolla in the female flowers falling off very early, or wanting. Stamens numerous, free. Male flowers without a rudimentary pistil. Branches downy, at least when young.—Species 2.
West Africa (Cameroons). Grossera Pax
Flowers in spicate or racemose inflorescences. Stamens 6-13. 22
22. Flowers monoecious. Calyx 5-partite. Stamens 10, united at the base.
Anthers attached by the back. Male flowers without a rudimentary pistil. Branches glabrous.—Species 1. Madagascar and Comoro
Islands. Tannodia Baill.
Flowers dioecious. 23
23. Branches glabrous. Anther-halves suspended from the connective.—Species
2. West Africa and Comoro Islands. Agrostistachys Dalz.
Branches hairy. Styles 2-cleft. Leaves stalked.—Species 2. East
Africa. Holstia Pax
24. (13.) Styles united to about the middle or beyond. 25
Styles free or united at the base only. 32
25. Styles united nearly to the top into a usually hollow column. 26
Styles united about to the middle, undivided. Ovary 3-celled. 31
26. Calyx of the female flowers entire or shortly toothed. Anthers 3-4-celled.
Ovary 1-2-, rarely 3-celled. Trees or shrubs.—Species 50. Tropical and South Africa. (Including Mappa Juss.) Macaranga Thouars
Calyx of the female flowers 4-12-partite. Anthers 2-celled. Ovary
3-4-, rarely 5-celled. 27
27. Flowers dioecious. Calyx of the female flowers 4-partite. Ovary 4-celled, winged. Style rather long, columnar, with a 4-lobed stigma. Seeds with an outgrowth at the hilum. Trees.—Species 1. West Africa
(Cameroons). Tetracarpidium Pax
Flowers monoecious. Calyx of the female flowers 5-12-, rarely 4-partite.
Seeds usually without an outgrowth. 28
28. Calyx of the male flowers 3-partite, of the female 5-6-partite. Stamens 3, with united filaments. Ovary 3-celled. Style united into a globose body. Climbing shrubs. Flowers in spikes.—Species 1. Madagascar. Sphaerostylis Baill.
Calyx of the male flowers 4-6-partite. Stamens 4-30. 29
29. Stamens 4-6. Rudimentary pistil of the male flowers columnar. Ovary
3-celled. Trees or shrubs, with stellate hairs. Leaves undivided, palmately nerved. Flowers in spikes.—Species 1. Madagascar and
Comoro Islands. (Including Niedenzua Pax). Adenochlaena Baill.
Stamens 8-30, inserted upon an elevated receptacle. Rudimentary pistil none. Shrubs or undershrubs, usually climbing. 30
30. Flowers in cymes surrounded by two large, brightly coloured bracts.
Anther-halves parallel. Style columnar.—Species 15. Tropical and
South Africa. Some are used for dyeing, in medicine, or as ornamental plants. Dalechampia L.
Flowers in racemes, without conspicuous bracts. Anther-halves spreading.
Climbing plants. Leaves undivided.—Species 5. Central and South
Africa. Plukenetia L.
31. Stem herbaceous or woody at the base only, usually climbing, often with stinging hairs. Stamens 3, rarely more.—Species 45. Tropical and
South Africa. Some are used medicinally. (Including Ctenomeria
Harv.) Tragia L.
Stem woody throughout. Stamens numerous, free.—Species 20. Tropics.
The fruits of some species are used for tanning. Pycnocoma Benth.
32. (24.) Filaments repeatedly branched. Anther-halves numerous, separate, globose. Tall herbs or shrubs. Leaves palmately lobed. Flowers monoecious.—Species 1 (R. communis L., castor-oil-plant). Spontaneous in the tropics, naturalized in other parts of Africa. An ornamental plant yielding fibre, fodder, and poisonous oily seeds used in medicine. Ricinus L.
Filaments not branched. 33
33. Anther-halves plainly separate, oblong or linear, often twisted. Filaments
6-20, free. Styles free, usually divided. Trees or shrubs. 34
Anther-halves contiguous or nearly so, oblong to globular. 35
34. Bracts of the female flowers leaf-like. Sepals of the female flowers 3-5, small. Stamens usually 8. Disc none. Male flowers spicate, female spicate, paniculate, or solitary.—Species 80. Tropical and South Africa.
Some are used as ornamental or medicinal plants. Acalypha L.
Bracts of the female flowers small. Sepals of the female flowers 4-6, broad. Disc absent in the male flowers, flat and lobed in the female.
Flowers spicate.—Species 4. West Africa. Mareya Baill.
35. Anthers 2-celled, at least after opening. 36
Anthers 3-4-celled, even after opening. Trees or shrubs. 57
36. Anther-halves oblong, attached lengthwise or above the middle. 37
Anther-halves ovoid or globose, attached by the base or the tip, rarely in the middle. 50
37. Stamens 3-10. Trees or shrubs. 38
Stamens numerous. 43
38. Calyx valvate in bud. Stamens 5-10; filaments united throughout.
Rudimentary pistil exceeding the staminal tube. Styles very short,
2-lobed. Trees. Leaves 3-foliolate. Flowers in panicles, monoecious.—Species
2. Cultivated in the tropics. They yield rubber (para-rubber):
(Siphonia Schreb.) Hevea Aubl.
Calyx closed in bud. Stamens 3-10; filaments free or united at the base only. Styles distinctly developed. Leaves simple, undivided. 39
39. Male flowers with a rudimentary pistil. Stamens 6-10. Filaments free, bent twice. Styles divided into many branches. Flowers monoecious.
Shrubs with stellate hairs. 40
Male flowers without a rudimentary pistil. Filaments united at the base.
Styles undivided or with 2 branches. Flowers usually dioecious. 41
40. Sepals of the female flowers 6, entire, united halfway up. Styles free.—Species
1. Island of Socotra. (Under Cephalocroton Hochst.) Cephalocrotonopsis Pax
Sepals of the female flowers pinnately dissected. Styles united at the base.—Species 8. East Africa to Transvaal, Madagascar, and German
South-west Africa. Cephalocroton Hochst.
41. Styles at first united, finally free. Seeds with an outgrowth at the hilum.
Glabrous shrubs. Leaves 3-5-nerved at the base. Male inflorescences catkin-like, springing from the old wood.—Species 5. Tropics. Some yield dye-stuffs. Lepidoturus Baill.
Styles free or nearly so. Seeds without an outgrowth. Male inflorescences spike- or panicle-like, axillary. 42
42. Styles united at the base, two-cleft. Trees. Leaves penninerved.—Species
2. Madagascar. (Including Orfilea Baill., under Alchornea
Swartz) Lautembergia Baill.
Styles free, undivided.—Species 10. Tropics to Delagoa Bay. Some of them yield dye-stuffs. Alchornea Swartz
43. (37.) Styles laciniate. Ovary nearly glabrous. Disc in the male flowers consisting of glands situated outside the stamens, in the female indistinct.
Sepals 5. Trees. Leaves penninerved, without stipules.
Flowers dioecious, the male in clusters arising from the old wood, the female in axillary racemes.—Species 1. East Africa. Crotonogynopsis Pax
Styles two-cleft or undivided, but usually ciliate within. Ovary usually hairy. Disc indistinct in the male flowers. Sepals 2-4, very rarely 5.
Flowers in spikes or panicles. 44
44. Styles two-cleft. 45
Styles undivided. 47
45. Flowers dioecious, in panicles. Calyx of the male flowers 2-partite. Disc indistinct. Plants clothed with stellate hairs. Leaves palminerved.—Species
5. Central Africa. Neoboutonia Muell. Arg.
Flowers monoecious, all or the female in spikes. Calyx of the male flowers
4-5-partite. Disc distinctly developed in the female flowers. Trees.
Leaves penninerved. 46
46. Disc of the female flowers expanded. Styles thick. Leafstalk rather
short. Stipules lanceolate, persistent.—Species 1. West Africa. Necepsia Prain
Disc of the female flowers cupular. Styles awl-shaped. Leafstalk very short. Stipules awl-shaped, deciduous. Spikes unisexual.—Species 1.
Madagascar. (Under Alchornea Swartz) Palissya Baill.
47. Calyx of the male flowers 2-partite. Stamens numerous. Styles thickish, united at the base. Shrubs. Leaves narrow, penninerved. Flowers in axillary spikes, monoecious.—Species 1. Equatorial West Africa. Neopycnocoma Pax
Calyx of the male flowers 3-5-partite. 48
48. Flowers in leaf-opposed spikes, monoecious. Calyx 4-partite. Styles 4.
Stem herbaceous. Leaves broad.—Species 2. Southern West Africa
(Amboland). Pseudotragia Pax
Flowers in axillary or terminal spikes or panicles. Stem woody. 49
49. Leaves narrow, penninerved. Flowers monoecious, in spikes. Calyx of the male flowers 3-partite. Styles thin.—Species 1. Central
Africa. Argomuellera Pax
Leaves broad, palminerved. Flowers usually dioecious.—Species 10.
Tropical and South Africa. (Including Echinus Lour.) Mallotus Lour.
50. (36.) Anther-halves attached at the middle. Stamens 6-12. Calyx
5-partite. Ovary 3-celled. Styles 3, united at the base, 2-cleft. Herbs.
Flowers in cymes.—Species 8. South Africa. (Including Paradenocline
Muell. Arg.) Adenocline Turcz.
Anther-halves attached at the base or the top. Styles undivided or many-cleft. 51
51. Anther-halves attached at the top, pendulous, spreading downwards.
Styles 2, rarely 3, undivided. Herbs or undershrubs. 52
Anther-halves attached at the base, erect, spreading upwards. 54
52. Stamens 8-20. Disc of the female flowers reduced to two scales. Calyx
3-partite. Leaves opposite.—Species 3. North Africa; also introduced in South Africa. Used as dye-plants, pot-herbs, and in medicine.
“Mercury.” Mercurialis L.
Stamens 2-7. Disc none. Flowers monoecious. Leaves alternate. 53
53. Calyx of the female flowers 3-partite. Stamens 2-3. Leaves narrow, entire. Flowers in clusters.—Species 1. South Africa. Seidelia Baill.
Calyx of the female flowers reduced to a single scale or absent. Stamens
4-7. Leaves broad, more or less toothed. Flowers in racemes.—Species
2. South Africa. Leidesia Muell. Arg.
54. Stem herbaceous. Flowers monoecious. Calyx of the female flowers imbricate in bud. Stamens 3-10. Disc of the female flowers reduced to 3-4 linear scales. Ovary 3-4-celled. Styles undivided.—Species
1. Central Africa. Micrococca Benth.
Stem woody. Flowers dioecious, rarely monoecious, but then calyx of the female flowers valvate in bud. Ovary 2-3-celled. 55
55. Styles undivided. Disc of the female flowers entire or lobed. Stamens 5
or more, usually numerous.—Species 25. Tropical and South Africa.
Several species yield timber or are used in medicine. Claoxylon Juss.
Styles many-cleft. Stamens 3-12. Flowers dioecious. Shrubs. Stipules spiny. 56
56. Disc of the female flowers consisting of numerous, more or less ciliate scales; also 3 staminodes present. Sepals of the female flowers broad.
Ovary 3-celled. Fruit a 3-celled capsule. Female flowers in pendulous spikes.—Species 1. Southern West Africa. Poggeophyton Pax
Disc of the female flowers consisting of 2 narrow scales; no staminodes.
Fruit a drupe. Female flowers in clusters.—Species 8. Central
Africa. Erythrococca Benth.
57. (35.) Disc of the female flowers formed of 3 petal-like scales. Styles recurved, appressed to the ovary, united at the base, 2-cleft. Ovary
3-celled. Stamens 3. Anthers 4-celled. Flowers dioecious, the male ones in spikes, the female solitary or 2-3 together. Leaves pinnately nerved.—Species 3. West Africa. Yielding timber. Hasskarlia Baill.
Disc absent. Styles erect or spreading. Flowers in spikes, racemes, or panicles. 58
58. Calyx of the female flowers 3-5-partite. Stamens numerous. Anthers
4-celled. Ovary 2-3-celled. Styles long and thin, 2-parted. Seed-coat leathery. Trees or shrubs. Inflorescence spicate or racemose.—Species
3. Central Africa. Cleidion Blume
Calyx of the female flowers entire or shortly toothed. Connective not prolonged. Ovary 1-2-, rarely 3-celled. Styles undivided, usually short and thick. Seed-coat crustaceous. Leaves usually palmately nerved. (See 26.). Macaranga Thouars
59. (12.) Corolla present in the male flowers. 60
Corolla absent in the male flowers. 66
60. Flowers in corymb- or panicle-like inflorescences composed of cymes, nearly always monoecious. Stamens 5 or more, all or the outer opposite the petals, all or the inner united below. [Tribe JATROPHEAE.] 61
Flowers solitary or in clusters or panicles, dioecious. Stamens free, but often inserted on a stalk-like process of the receptacle. Shrubs or trees. [Tribe CLUYTIEAE.] 62
61. Flowers dioecious. Petals free. Stamens 16-17, the five outer nearly free, the inner irregularly united. Seeds without an outgrowth. Leaves undivided.—Species 2. East Africa. Neojatropha Pax
Flowers monoecious. Stamens in 2-6 whorls, usually 8-10. Seeds with an outgrowth at the hilum.—Species 50. Central and South Africa; two species cultivated and naturalized in the tropics. Several species yield gum, oil, and medicaments; some are poisonous or used as garden- or hedge-plants. Jatropha L.
62. Stamens 5. Male flowers with a rudimentary pistil. Petals free. Flowers
solitary or in clusters in the axils of the leaves. Leaves undivided. 63
Stamens 12 or more. Male flowers without a rudimentary pistil. Flowers in panicles. 64
63. Stamens opposite the sepals, inserted upon a flat receptacle, free. Fruit
a drupe.—Species 1. West Africa. Microdesmis Planch.
Stamens opposite the petals, inserted upon a stalk-like receptacle. Fruit
a capsule.—Species 40. South and Central Africa. Some are used as ornamental plants. Cluytia L.
64. Petals free. Stamens free. Fruit a capsule. Leaves undivided, pinnately nerved. Shrubs.—Species 1. Equatorial West Africa (Congo). Mildbraedia Pax
Petals united below. Fruit a drupe. Leaves lobed or dissected, palmately nerved at the base. Trees. 65
65. Leaves lobed.—Species 1. Madagascar. Givotia Griff.
Leaves dissected.—Species 3. West Africa. Yield timber and fat from the seeds. Ricinodendron Muell. Arg.
66. (59.) Stamens 1-4, rarely more, and then ovary many-celled. Disc little developed or wanting. Male flowers without a rudimentary pistil.
Style-branches undivided. [Tribe HIPPOMANEAE.] 67
Stamens 5 or more. Ovary 2-4-celled. Style-branches two-cleft or lobed. Sepals 4-8. Shrubs or trees. 74
67. Stamens 8 or more. Calyx cup-shaped, almost entire. Ovary many-celled.
Style columnar, many-branched at the top. Fruit a capsule.
Trees. Inflorescence spicate; bracts adnate to the rachis throughout their whole length, at first enclosing the flower-buds. Flowers monoecious.—Species
1 (H. crepitans L., sandbox-tree). Naturalized in the tropics. Ornamental tree, yielding oil and medicaments; the fruits are used as sand-boxes; the juice is poisonous. Hura L.
Stamens 1-4. Ovary 2-4-celled. Bracts adnate to the rachis of the inflorescence by their base only. 68
68. Stamens 1-3, the filaments entirely or almost entirely united. Shrubs or trees. Flowers monoecious. 69
Stamens 2-4, the filaments free or united at the base only. Styles free or united at the base. Ovary 2-3-celled. 71
69. Calyx 3-lobed. Stamens 1-3; filaments free at the top, connective not broadened. Ovary 3-4-celled. Styles united high up. Fruit a capsule.
Seeds with a large outgrowth at the hilum. Flowers in panicles.—Species
3. Central Africa. Maprounea Aubl.
Calyx 4-5-parted. Stamens 2-3; filaments united into a short column.
Anthers turned outwards. Ovary 2-3-celled. Fruit a capsule or a drupe. Seeds without an outgrowth. 70
70. Calyx-segments broad. Connective broadened, peltate. Styles united high up. Flowers in panicles.—Species 2. Tropics. Omphalea L.
Calyx-segments narrow. Connective not broadened. Styles free or
united at the base. Flowers in spikes.—Species 2. Central Africa. Excoecariopsis Pax
71. Calyx of the male flowers 2-3-toothed or -lobed. Inflorescence terminal.
Bracts with two glands. Flowers monoecious. 72
Calyx of the male flowers 2-5-parted. Fruit a capsule with a persistent central column. 73
72. Ripe carpels separating from a 3-parted central column. Seeds without an outgrowth.—Species 10. Tropical and South Africa. They yield timber; one species (S. sebiferum Roxb.) is cultivated for its oily seeds.
(Including Conosapium Muell. Arg.). Sapium P. Browne
Ripe carpels separating from the base of the pericarp, leaving no central column. Seeds with an outgrowth at the hilum.—Species 5. Tropical and South Africa. Some are poisonous. Stillingia L.
73. Seeds with an outgrowth at the hilum. Flowers monoecious. Inflorescences terminal or terminal and lateral. Leaves alternate.—Species
3. Central Africa. (Cnemidostachys Mart.) Sebastiania Spreng.
Seeds without an outgrowth at the hilum. Flowers usually dioecious.
Inflorescences usually lateral.—Species 20. Tropical and South Africa.
Some are poisonous or are used as ornamental plants. (Including
Taenosapium Muell. Arg.) Excoecaria L.
74. (66.) Flowers in racemes, monoecious, with a disc. Sepals of the male flowers evidently united below. Stamens 10, free. Leaves palmately divided, sometimes alternating with undivided ones.—Species 3.
Cultivated in the tropics. M. Glaziovii Muell. Arg. yields rubber,
M. utilissima Pohl and M. dulcis Pax (cassava or mandioc-plants) furnish vegetables, medicaments, and edible roots, from which meal, starch (tapioca), and a spirituous drink are prepared. Manihot Adans.
Flowers in glomerules, dioecious, rarely monoecious, but then without a disc. Sepals of the male flowers free or nearly so. Leaves undivided.
[Tribe GELONIEAE.] 75
75. Sepals 5. Filaments free. Male flowers without a disc and without a rudimentary pistil.—Species 6. Tropical and South Africa. (Ceratophorus
Sond., including Suregada Roxb.) Gelonium Roxb.
Sepals of the female flowers 7-8, the inner petaloid. Filaments united.—Species
1. West Africa. Chaetocarpus Thwait.
76. (1.) Calyx of the male flowers with valvate aestivation. Stamens 5-7.
Male flowers with a rudimentary pistil. Shrubs or trees. 77
Calyx of the male flowers with imbricate or open aestivation. 81
77. Petals absent. Disc none. Styles 2, undivided. Ovary-cells 2, each with an incomplete partition.—Species 1. West Africa. Martretia Beille
Petals small. Disc outside the stamens. Styles 2-parted. Ovary-cells undivided. [Tribe BRIDELIEAE.] 78
78. Ovary 2-celled. Styles 2. Stamens borne upon a short androphore.
Leaf-veins of the third order almost parallel. 79
Ovary 3-celled. Styles 3. Disc of the female flowers cup-shaped. Fruit a
capsule. Leaf-veins of the third order netted. 80
79. Disc of the female flowers bottle-shaped, enclosing the ovary to the top.
Inflorescence paniculate.—Species 1. East Africa. (Under Bridelia
Willd.) Neogoetzea Pax
Disc of the female flowers double, the outer cup-shaped, adhering to the calyx, the inner consisting of 5 scales. Fruit usually a drupe.—Species
25. Tropical and South-east Africa. Some species yield dye-stuffs.
(Including Gentilia Beille) Bridelia Willd.
80. Receptacle of the male flowers elevated, forming a short androphore.—Species
10. Tropics. Cleistanthus Hook.
Receptacle not prolonged into an androphore. Flowers clustered, dioecious.—Species
1. Madagascar and Comoro Islands. Stenonia Baill.
81. (76.) Anthers 4-celled, even after opening, numerous. Filaments united.
Male flowers with 5 sepals and 3 valvate petals. Ovary 3-4-celled.
Styles 3, undivided. Carpels enlarging and separating after the time of flowering. Downy shrubs. Leaves without stipules. Flowers in axillary glomerules.—Species 1. South-east Africa. [Tribe JUNODIEAE.] Junodia Pax
Anthers 2-celled, at least after opening. 82
82. Seeds with a very small embryo. Fruit an oblong drupe. Ovary 2-celled.
Styles 2, undivided. Male flowers with 9-18 free, central stamens, without a disc and without a rudimentary pistil. Corolla none. Flowers dioecious, in racemes. Trees.—Species 1. West Africa. [Tribe
DAPHNIPHYLLEAE] Daphniphyllum Blume
Seeds with a large embryo. Ovary-cells and styles usually 3; if 2, then stamens 2-6 or surrounding a central disc. [Tribe PHYLLANTHEAE.] 83
83. Corolla present, at least in the flowers of one sex. 84
Corolla absent. 95
84. Stamens 8-10. Anthers opening outwards. Sepals, petals, and carpels
4-5. Flowers dioecious, in glomerules. Trees.—Species 1. South
Africa. Yields timber. Heywoodia Sim
Stamens 4-5. [Subtribe ANDRACHNINAE.] 85
85. Flowers 3-merous, dioecious. Petals exceeding the sepals in the male flowers, absent in the female. Male flowers without a rudimentary pistil. Stamens 6, each surrounded at the base by a gland; anthers opening transversely. Ovary 4-5-celled. Shrubs. Flowers in glomerules.—Species
1. East Africa (Somaliland). Bricchettia Pax
Flowers 4-6-merous. Male flowers with a rudimentary pistil. 86
86. Ovary 5-celled. Styles 5, two-cleft. Disc cup-shaped, lobed in the male flowers, entire in the female. Stamens inserted upon a short androphore.
Petals exceeding the sepals. Flowers fascicled, monoecious. Shrubs.—Species
1. Seychelles. (Under Savia Willd.) Wielandia Baill.
Ovary 3-celled. Styles or sessile stigmas 3. 87
87. Styles very short, undivided. 88
Styles well developed, two-cleft. 90
88. Flowers monoecious, in spikes or fascicles. Petals short. Rudimentary pistil 3-lobed. Stigmas thick. Seeds solitary in each cell, exalbuminous, with thick-fleshy cotyledons. Trees or shrubs.—Species 6. Tropics. Amanoa Aubl.
Flowers dioecious, in panicles. Fruit a loculicidal capsule. Trees. 89
89. Panicles terminal. Petals small. Disc of the male flowers of separate glands. Rudimentary pistil obconical, flattened at the top. Seeds with
a spongy coat, scanty albumen, and flat cotyledons.—Species 2.
Equatorial regions. Megabaria Pierre
Panicles axillary. Petals large. Disc of the male flowers cupular. Rudimentary pistil narrowed above. Seeds with copious albumen.—Species
1. Equatorial West Africa. Centroplacus Pierre
90. Stamens inserted upon a prolonged, stalk-like receptacle. Petals shorter than the sepals. Disc and ovary densely woolly. Seeds with scanty albumen and folded cotyledons. Shrubs. Flowers dioecious, the male ones fascicled, the female solitary.—Species 1. South Africa. Lachnostylis Turcz.
Stamens inserted upon a receptacle which is not stalk-like. 91
91. Stamens inserted upon the disc. Seeds exalbuminous, with folded cotyledons.
Trees or shrubs. Flowers in fascicles.—Species 1. Equatorial
West Africa. (Pentabrachium Muell. Arg.) Actephila Blume
Stamens inserted inside the disc round the rudimentary pistil. Seeds with copious albumen. 92
92. Male flowers without a corolla, with 4 sepals and 6 stamens. Female flowers with 2 sepals and 5 petals. Flowers dioecious, the male in glomerules, the female solitary. Shrubs or trees.—Species 1. West
Africa (Congo). Neochevaliera Beille
Male flowers with a corolla, rarely without, but then with 5 sepals and 5 stamens. Flowers dioecious, the male in spikes, racemes, or panicles, or monoecious. 93
93. Lobes of the disc alternating with the petals. Flowers monoecious, in glomerules or the female solitary. Shrubs.—Species 8. Madagascar and neighbouring islands. (Under Savia Willd.) Petalodiscus Baill.
Lobes of the disc opposite the petals. Male flowers in spikes, racemes, or fascicles. 94
94. Flowers monoecious. Anther-halves adnate lengthwise. Rudimentary pistil of the male flowers columnar or 3-partite. Styles short. Herbs, undershrubs, or shrubs.—Species 6. Andrachne L.
Flowers dioecious. Anther-halves at first suspended from the thick connective.
Rudimentary pistil thick, usually obovate. Styles long.
Shrubs or trees.—Species 9. West Africa and Madagascar. Thecacoris Juss.
95. (83.) Leaves digitate. Male flowers in glomerules, with a 5-8-partite calyx. Trees. [Subtribe BISCHOFIINAE.] 96
Leaves simple, undivided. 98
96. Leaflets 1-3. Flowers monoecious. Stamens 14-15.—Species 1.
Southern West Africa (Angola). Aristogeitonia Prain
Leaflets 5-7. Flowers dioecious. Stamens 4-10. 97
97. Leaves opposite. Leaflets stalked. Fruit a capsule.—Species 1. West
Africa. Yields timber (African teak). Oldfieldia Hook.
Leaves alternate. Leaflets sessile. Male flowers with a 6-8-cleft calyx and 6-8 stamens. Female flowers solitary, with 3 bracteoles, a disc consisting of 6-7 scales, a 2-celled ovary, and 2 short, thick, undivided styles. Fruit a drupe.—Species 1. Southern West Africa (Angola). Paivaeusa Welw.
98. Leaves opposite or whorled. Flowers dioecious, the male in fascicles or panicles, the female solitary. Stamens numerous. Disc none. Fruit
a capsule. Trees. [Subtribe TOXICODENDRINAE.] 99
Leaves alternate. 100
99. Sepals 2-5. Stamens inserted upon a stalk-like receptacle. Styles united high up.—Species 1. Southern East Africa (Mosambic).
Yields timber. Androstachys Prain
Sepals 5-12. Stamens inserted upon a flat receptacle. Styles united at the base only.—Species 1. South Africa (Cape Colony). Fruit poisonous. (Hyaenanche Lamb.) Toxicodendron Thunb.
100. Male flowers in catkins, spikes, racemes, or panicles, more rarely in heads or umbels with a calyx-like involucre. Flowers dioecious. [Subtribe
ANTIDESMINAE.] 101
Male flowers in axillary glomerules, fascicles, or short cymes, rarely in umbels without an involucre. 112
101. Male flowers in umbels or heads with a calyx-like involucre, female solitary.
Male flowers without a disc, but with a rudimentary pistil. Stamens
4-5. Ovary 2-4 celled. Styles branched. Fruit fleshy, indehiscent.
Trees.—Species 30. Tropics. Some yield timber or edible fruits. Uapaca Baill.
Male flowers in spikes, racemes, or panicles without an involucre. 102
102. Ovary 1-celled. Fruit a drupe. Trees or shrubs. 103
Ovary 2-5-celled. 105
103. Styles 3, 2-lobed. Male flowers with a disc. Stamens 2-5.—Species
25. Tropical and South-east Africa. Some yield timber and dye-stuffs. Antidesma L.
Style 1, undivided. Male flowers without a disc. 104
104. Sepals in the male flowers 3-5. Stamens 3-5. Disc of the female flowers ring-shaped.—Species 2. Madagascar. Cometia Thouars
Sepals in the male flowers 6-8. Stamens numerous. Disc none.—Species
1. Equatorial West Africa. The seeds yield oil. Plagiostyles Pierre
105. Ovary 2-celled. Male flowers with a rudimentary pistil. Trees or shrubs. 106
Ovary 3-, rarely 4-5-celled. 108
106. Ovary and fruit winged. Styles long, undivided. Disc none. Stamens
4-6.—Species 12. Central and South Africa. Hymenocardia Wall.
Ovary and fruit not winged. Styles short. 107
107. Disc in the male flowers consisting of 5 scales, in the female cup-shaped, entire. Stamens 5. Fruit one-seeded.—Species 4. West Africa and
Upper Nile. Maesobotrya Benth.
Disc, especially in the female flowers, little developed or absent. Styles shortly lobed. Fruit several-seeded.—Species 10. West Africa. Baccaurea Lour.
108. Disc indistinct or wanting. Styles short, very shortly lobed. (See 107.) Baccaurea Lour.
Disc distinctly developed. Stamens 4-5. 109
109. Disc entire or nearly so. Styles undivided, united high up. Rudimentary pistil salver-shaped. Shrubs.—Species 1. Equatorial regions. Baccaureopsis Pax
Disc lobed or divided. Styles more or less deeply two-cleft. 110
110. Stem herbaceous or woody at the base only. Stipules hair-like. Flowers very small. Rudimentary pistil salver-shaped. Styles free, thick, 2-cleft.—Species
5. Central Africa. Cyathogyne Muell. Arg.
Stem woody. Rudimentary pistil not salver-shaped. 111
111. Stipules large, kidney-shaped. Inflorescence springing from the old wood. Seeds with an aril.—Species 5. West Africa. (Under Maesobotrya
Benth.) Staphysora Pierre
Stipules not kidney-shaped. Flowers 5-merous. Anther-halves at first suspended from the thickened connective. Styles long. (See 94.) Thecacoris Juss.
112. (100.) Styles or sessile stigmas much broadened, sometimes wholly united.
Flowers dioecious. Disc present. Fruit indehiscent. Trees or shrubs.
[Subtribe DRYPETINAE.] 113
Styles or style-branches rather thin or broadened at the apex only. [Subtribe
PHYLLANTHINAE.] 115
113. Stamens 3. Ovary 1-celled. Stigmas peltate, nearly sessile. Disc cup-shaped in the male flowers, ring-shaped in the female. Sepals unequal.—Species
1. West Africa. Sibangea Oliv.
Stamens 4 or more. 114
114. Fruit 1-seeded. Ovary 1-2-celled. Stamens usually 4.—Species 4.
Central Africa. Drypetes Vahl
Fruit 2-4-seeded. Ovary 2-4-celled. Stamens usually numerous.—Species
20. Tropical and South Africa. Cyclostemon Blume
115. Male flowers with a rudimentary pistil and a disc usually divided into glands. 116
Male flowers without a rudimentary pistil. 120
116. Receptacle of the male flowers prolonged into an androphore. Stamens
5-6. Shrubs, undershrubs, or herbs. 117
Receptacle not prolonged into an androphore. Disc of the male flowers divided into glands alternating with the sepals, rarely entire. Seeds without an outgrowth at the hilum. Shrubs and trees. 118
117. Disc of the male flowers nearly entire, of the female divided into 5 glands alternating with the sepals. Fruit a drupe. Seeds with an outgrowth at the hilum. Shrubs. Male inflorescence many-flowered.—Species 3.
Central Africa. Pseudolachnostylis Pax
Disc of the male flowers 5-lobed or divided into 5 glands opposite the sepals. Fruit a capsule. Seeds without an outgrowth at the hilum.
Flowers monoecious, fascicled.—Species 4. Central Africa. Cluytiandra Muell. Arg.
118. Disc of the male flowers slightly lobed. Styles undivided. Flowers monoecious, large. Stipules large.—Species 1. German East Africa. Zimmermannia Pax
Disc of the male flowers deeply lobed or divided. Styles two-cleft.
Flowers usually dioecious. 119
119. Anthers opening outwards. Disc of the female flowers lobed. Seeds grooved on the ventral face; testa thick; embryo curved.—Species 8.
Tropical and South Africa. Some yield timber. (Under Securinega
Juss.) Flueggea Willd.
Anthers opening inwards or laterally. Disc of the female flowers undivided.
Seeds not grooved; testa thin; embryo straight.—Species
6. Some of them yield timber. Securinega Juss.
120. Disc present. 121
Disc absent. Shrubs or trees. 124
121. Disc of the male flowers consisting of 5-6 scales adnate below to the sepals which consequently appear much thickened. Stamens 3. Filaments very short, united. Anthers opening outwards. Style-branches
2-cleft. Flowers monoecious. Herbs or undershrubs.—Species 1.
Madagascar and neighbouring islands. Agyneia Vent.
Disc of the male flowers not adnate to the sepals; hence sepals not much thickened. 122
122. Stamens 2-10. Styles usually two-cleft.—Species 80. Tropical and
South Africa; one species naturalized in Egypt. Some of them serve as garden- or hedge-plants or yield timber, tanning and dyeing materials, edible fruits, and medicaments. (Including Cicca L. and Pleiostemon
Sond.) (Plate 80.) Phyllanthus L.
Stamens 12-18. Disc many-lobed or many-parted. Styles 3. Shrubs or trees. 123
123. Flowers monoecious. Sepals 5. Disc lobed. Styles entire or notched, flattened.—Species 1. Madagascar and Comoro Islands. Humblotia Baill.
Flowers monoecious with 6 sepals, or dioecious with 5. Disc deeply divided. Styles two-cleft. Stipules gland-like.—Species 2. Equatorial
West Africa. Lingelsheimia Pax
124. Flowers monoecious. Calyx 6-lobed. Stamens 3; filaments united; anthers opening outwards. Male flowers in glomerules.—Species 1.
Naturalized in the Mascarene Islands. (Melanthesopsis Muell. Arg.) Breynia Forst.
Flowers dioecious. Calyx 5-parted. Stamens 5; filaments free; anthers opening inwards. Male flowers in umbels.—Species 1. Madagascar. Leptonemea Juss.

[FAMILY 123.] CALLITRICHACEAE

Herbs. Leaves opposite, simple, entire. Flowers solitary or in clusters in the leaf-axils, minute, without a perianth, but sometimes with two bracteoles, monoecious. Stamens 1. Anther 2-celled. Ovary 4-celled. Ovules solitary in each cell, pendulous, inverted, with a single coat and a ventral raphe. Styles 2, free, awl-shaped. Fruit separating into 4 drupe-like mericarps. Seeds albuminous; embryo axile. (Under HALORRHAGIDACEAE.)

Genus 1, species 6. North and South Africa and high mountains of Central
Africa; one species also naturalized in Madagascar and the Mascarene
Islands. Callitriche L.

ORDER SAPINDALES