1. Plants without green colour, parasitic. Stem herbaceous, twining. Leaves reduced to scales or wanting. Flowers small, in fascicles. Corolla imbricate in bud, usually with scales at the throat. Ovary completely or incompletely 2-celled with 4 ovules. Embryo twisted, without cotyledons.—Species 25. Some of them are noxious weeds, several are used medicinally. “Dodder.” [Tribe CUSCUTEAE.] Cuscuta L.
Plants of green colour. Corolla plicate or valvate in bud, rarely (Cressa) imbricate, but then stem shrubby. Embryo straight or slightly curved, with 2 cotyledons. 2
2. Calyx minute. Ovary 1-celled with 2 ovules. Styles 2. Fruit 1-seeded, ripening underground. Creeping herbs. Leaves kidney-shaped.
Flowers solitary.—Species 1. Abyssinia. (Nephrophyllum A. Rich.) Hygrocharis Hochst.
Calyx distinctly developed. 3
3. Ovary lobed or divided. Ovules 4. Styles 2, inserted between the lobes of the ovary. Sepals more or less united below. Flowers solitary.
Creeping or prostrate herbs. [Tribe DICHONDREAE.] 4
Ovary entire. Sepals free, rarely (Rapona) united below, but then ovules 2, style 2-cleft, flowers in panicles, and stem twining. 5
4. Ovary and fruit 2-lobed. Corolla deeply cleft, yellow. Sepals nearly free.
Leaves kidney-shaped.—Species 1. Tropical and South Africa, also naturalized in the Island of Madeira. Dichondra Forst.
Ovary and fruit 4-parted. Corolla slightly lobed. Sepals evidently united below.—Species 4. South Africa and Abyssinia. Falkia L. f.
5. Styles 2, free or united below. 6
Style 1, undivided; stigmas 2, continuous at the base, or a single stigma. 16
6. Flowers in axillary or terminal and axillary racemes or panicles. Twining shrubs. [Tribe PORANEAE.] 7
Flowers solitary, in axillary cymes, or in terminal spikes or heads. Ovules 4.
[Tribe DICRANOSTYLEAE.] 10
7. Sepals united below, not enlarged in the fruit. Corolla entire, with plicate aestivation. Filaments broadened and hairy at the base. Disc large, cup-shaped. Ovary incompletely 2-celled, with 1 ovule in each cell.
Style 2-cleft at the top, with capitate stigmas.—Species 1. Madagascar. Rapona Baill.
Sepals free. Corolla more or less lobed. Disc small. Ovary 1-2-celled,
with 2 ovules in each cell. Style deeply 2-cleft or divided to the base. 8
8. Sepals unequal, the two outer ones much enlarged in the fruit. Corolla deeply lobed. Disc cup-shaped. Ovary 1-celled. Ovules 2. Style
2-cleft; stigmas linear or oblong.—Species 1. Equatorial West
Africa (Cameroons). Dipteropeltis Hallier
Sepals about equal. Disc ring-shaped or indistinct. Ovary completely or incompletely 2-celled. Ovules 4. Style divided to the base; stigmas capitate or peltate. 9
9. Inflorescence composed of racemes. Bracts surrounding the fruit much enlarged. Corolla deeply lobed, induplicate-valvate in bud. Ovary incompletely septate. Stigmas peltate.—Species 2. West Africa. Neuropeltis Wall.
Inflorescence composed of fascicles. Bracts not much enlarged in the fruit.
Stigmas capitate.—Species 2. East Africa. Porana Burm.
10. Flowers dioecious. Sepals enlarged in the fruit. Corolla deeply cleft.
Stigmas horse-shoe-shaped. Shrubs with small leaves. 11
Flowers hermaphrodite. 12
11. Sepals of the female flowers distinctly unequal, the outer much larger than the inner. Flowers usually 4-merous.—Species 4. Northern East
Africa. Hildebrandtia Vatke
Sepals nearly equal. Flowers 5-merous. Styles united at the base.
Seeds 2. Branches stiff.—Species 2. Northern East Africa. Cladostigma Radlk.
12. Stigmas filiform, 2-parted. Erect herbs or undershrubs. Leaves small.—Species
4. Tropical and South Africa. Evolvulus L.
Stigmas globose or peltate, usually entire. Shrubs. 13
13. Anthers and stigmas projecting beyond the corolla-tube. Sepals subequal.
Corolla small, cleft to the middle, imbricate in bud. Fruit 1-seeded.
Prostrate or ascending small shrubs. Leaves small. Flowers in terminal spikes.—Species 1. Tropical and North Africa. Used medicinally. Cressa L.
Anthers and stigmas concealed within the corolla-tube. Corolla folded in bud. 14
14. Corolla small, funnel-shaped. Sepals subequal. Filaments glabrous, broadened at the base and usually toothed on each side. Stigmas more or less peltate. Fruit 4-seeded. Erect or procumbent, small shrubs.
Leaves small.—Species 20. Tropical and South Africa. (Under
Breweria R. Br.) Seddera Hochst.
Corolla large or medium-sized. Filaments not toothed, but usually hairy at the base. Stigmas more or less globose. Twining shrubs. Leaves large or of moderate size. Flowers solitary or in axillary cymes or terminal panicles. 15
15. Sepals herbaceous or leathery, subequal, or the inner somewhat smaller, not enlarged after flowering. Corolla funnel-shaped. Fruit 4-seeded.—Species
10. Tropics. (Under Breweria R. Br.) Bonamia Thouars
Sepals membranous or scarious, the inner much smaller than the outer, enlarged after flowering. Corolla bell- or pitcher-shaped. Fruit 1-seeded.—Species
12. Tropics. (Under Breweria R. Br.) Prevostea Choisy
16. (5.) Flowers in axillary racemes. Outer sepals much larger than the inner, together with the 3 bracteoles much enlarged in the fruit. Corolla small, deeply lobed. Anthers exserted. Disc cushion-shaped. Ovary
1-celled. Ovules 2. Stigma 1. Twining herbs. Leaves cordate.—Species
2. Madagascar. Cardiochlamys Oliv.
Flowers solitary or in axillary, sometimes raceme-like cymes, rarely in terminal spikes or panicles. Ovules 4 or more. 17
17. Ovules numerous. Stigmas 2. Filaments curved; anthers much exserted.
Corolla entire. Flowers solitary. Trees.—Species 1. Madagascar.
Yields timber. Humbertia Lam.
Ovules 4-6. Herbs, undershrubs, or shrubs. 18
18. Pollen-grains smooth. Corolla usually gradually widened from below upwards and without well defined midpetaline areas. Anthers included.
Ovules 4. [Tribe CONVOLVULEAE.] 19
Pollen-grains spinous. Corolla irregularly widened, with 5 longitudinal midpetaline areas limited by prominent nerves. 26
19. Ovary 1-celled, sometimes with an incomplete partition. 20
Ovary 2-celled, rarely (Merremia) 4-celled. 22
20. Stigmas globose. Sepals lanceolate, unequal, not enlarged after flowering.
Corolla bell-shaped, shortly lobed. Stamens unequal. Fruit one-seeded, indehiscent. Prostrate herbs. Leaves lobed.—Species 1.
East Africa (Somaliland). Hyalocystis Hallier
Stigmas ovate or oblong, flattened. Fruit 4-seeded, 4-valved. 21
21. Sepals unequal. Corolla bell-shaped, entire. Twining herbs. Leaves ovate-cordate. Bracts small.—Species 1. Tropical and South-east
Africa. (Shutereia Choisy). Hewittia Wight & Arn.
Sepals about equal. Corolla slightly lobed. Twining or prostrate herbs.
Leaves sagittate or hastate. Bracts large, leaf-like.—Species 5.
North, South, and East Africa. Some of them have edible root-stocks or serve as ornamental or medicinal plants. (Under Convolvulus
L.) Calystegia R. Br.
22. Stigmas filiform. Disc present. Corolla funnel-shaped without well-defined midpetaline areas.—Species 70. Some of them yield an essential oil used in perfumery or serve as ornamental or medicinal plants. “Bind-weed.” (Including Rhodorrhiza Webb et Berth.) Convolvulus L.
Stigmas elliptic, disciform, or globose. 23
23. Stigmas elliptic or disciform. Disc indistinct or wanting. Corolla with well-defined midpetaline areas, blue, more rarely white or reddish.
Sepals not decurrent on the pedicel, usually subequal. Herbs or
under-shrubs.—Species 5. Tropical and South Africa. Some are used as vegetables. (Plate 131.) Jacquemontia Choisy
Stigmas more or less globose. Corolla white or yellow. 24
24. Sepals very unequal, the outer much larger than the inner and decurrent on the pedicel, herbaceous. Corolla tubular-funnel-shaped, entire, hairy outside, with well-defined midpetaline areas. Disc obscure.
Twining herbs. Leaves oblong.—Species 1. Tropical and South-east
Africa. (Under Ipomoea L.) Aniseia Choisy
Sepals nearly equal, usually leathery or parchment-like. 25
25. Fruit opening by a lid. Flowers large. Sepals much enlarged in the fruit.
Corolla without sharply limited midpetaline areas and without dark lines. Twining herbs. Stem usually winged. Leaves broad.—Species
6. Tropics. Some are used medicinally. (Under Merremia Dennst. or
Ipomoea L.) Operculina Manso
Fruit opening by 4 valves. Corolla bell-shaped; midpetaline areas usually marked with 5 dark-violet lines. Stem rarely winged.—Species
25. Tropical and South Africa. Some species yield fodder and a substitute for coffee. (Under Convolvulus L. or Ipomoea L.) Merremia Dennst.
26. (18.) Fruit fleshy, mealy, or dry, and then with a woody or crusty rind, indehiscent. Ovary 2-4-celled. Stigmas globose or elliptical. Disc cupular. Shrubs. [Tribe ARGYREIEAE.] 27
Fruit dry, with a membranous leathery or parchment-like rind, dehiscing by 4-6 valves, rarely (Ipomoea) indehiscent. [Tribe IPOMOEEAE.] 29
27. Fruit fleshy or mealy. Corolla more or less bell-shaped. Stigmas 1-2, globose. Stem twining. Leaves cordate.—Species 2. Naturalized in the Mascarene Islands. Ornamental plants. Argyreia Lour.
Fruit dry. Corolla funnel- or salver-shaped. Stigmas 2, globose or elliptical. 28
28. Fruit with a woody rind, 1-celled, usually 1-seeded. Seeds glabrous.—Species
10. Central and South Africa and Canary Islands. (Including
Legendrea Webb, under Ipomoea L.) Rivea Choisy
Fruit with a crustaceous rind, 4-celled, 4-seeded, enveloped by the adnate sepals. Seeds large, brown-velvety. Ovary 4-celled. Corolla funnel-shaped.
Stem twining. Leaves cordate.—Species 4. Tropics. (Under
Argyreia Lour., Rivea Choisy, or Ipomoea L.) Stictocardia Hallier
29. Filaments with a large scale at the base within. Corolla shortly lobed.
Disc cupular. Ovary 2-celled. Ovules 4. Stigma capitate, 2-lobed.
Twining herbs. Leaves usually lobed. Flowers in axillary cymes. 30
Filaments without a scale at the base. 31
30. Sepals distinctly unequal. Corolla bell-shaped. Fruit 2-valved. Seed-coat granular. Flowers medium-sized.—Species 1. East Africa. Lepistemonopsis Dammer
Sepals nearly equal. Corolla pitcher-shaped. Fruit 4-valved. Seed-coat smooth. Flowers small.—Species 2. Central Africa. Noxious to
cattle. Lepistemon Blume
31. Stigmas 2, oblong or linear. Corolla funnel-shaped, white red or violet.
Seeds hairy. Plants with star-shaped hairs.—Species 20. Central and South-east Africa. Astrochlaena Hallier
Stigmas 1-3, more or less capitate. Plants without star-shaped hairs. 32
32. Pedicels club-shaped, becoming large and fleshy in the fruit. Sepals cartilaginous, pointed or awned. Corolla very large, regular, salver-shaped, white or violet. Ovary 2-celled. Stigma biglobose. Seeds glabrous. Twining herbs. Leaves cordate or lobed.—Species 2.
Naturalized in the tropics. Ornamental and medicinal plants; the young seeds are edible. (Under Ipomoea L.) Calonyction Choisy
Pedicels not much thickened in the fruit. 33
33. Anthers and stigmas projecting beyond the corolla-tube. Ovary 4-celled.
Corolla scarlet, medium-sized, salver-shaped, usually somewhat irregular.
Sepals herbaceous, ending in a short point. Seeds glabrous or downy.
Twining herbs. Leaves cordate, lobed, or pinnately dissected. Flowers in cymes.—Species 2. Naturalized in the tropics and in South Africa.
Ornamental plants. (Under Ipomoea L.) Quamoclit Tourn.
Anthers and stigmas usually concealed within the corolla-tube. Ovary
1-3-celled, rarely 4-celled, but then corolla not scarlet and salver-shaped.
Corolla regular.—Species 220. Some of them (especially the sweet potato, I. Batatas Lam.) yield edible tubers from which also starch and brandy are prepared, besides vegetables, fodder, and medicaments, others are used in preparing rubber, for fixing sand-dunes, or as ornamental plants. (Including Batatas Choisy and Pharbitis Choisy). Ipomoea L.
SUBORDER BORRAGININEAE
[FAMILY 203.] HYDROPHYLLACEAE
Erect herbs or undershrubs. Juice not milky. Leaves alternate, herbaceous, undivided, without stipules. Flowers solitary or in cymes or panicles, regular, hermaphrodite. Sepals united at the base, narrow, imbricate in bud. Corolla more or less bell-shaped, 5-12-cleft, imbricate in bud. Stamens as many as and alternating with the corolla-lobes, inserted on the lower part of the corolla-tube, equal or subequal in length. Anthers attached at the back, opening inwards by two longitudinal slits. Disc none. Ovary superior, completely or almost completely 2-celled, with numerous descending, inverted ovules in each cell. Styles 2, free or partly united. Fruit a capsule opening by 2-4 valves or irregularly. Seeds with a small, straight embryo and copious albumen.—Genera 2, species 8. Tropical and South Africa.
Flowers 5-merous. Corolla blue. Styles free. Placentas free from the pericarp. Seed-coat wrinkled. Glandular-hairy or glabrous plants.—Species
6. Tropics. [Tribe HYDROLEEAE.] Hydrolea L.
Flowers 8-12-merous. Corolla white or yellow. Styles united below.
Placentas attached to the valves of the fruit. Seed-coat bladdery.
Spinous plants.—Species 2. South Africa to Damaraland. [Tribe
PHACELIEAE.] Codon L.
CONVOLVULACEAE.
FLOW. PL. AFR.
Pl. 131.
J. Fleischmann del.