Here is a list of one-hundred families of dicotyledoneae.
100 Families of Dicotyledoneae
Family # 1. Myricaceae (Bayberry):
General Features of the Family:
Habit – Shrubs or trees, deciduous or evergreen.
Leaves – Alternate, short petioled, simple, rarely pinnatifid, stiff, contain yellow, aromatic resin glands.
Inflorescence – Dense catkins.
Flowers – Bracteate, perianthless, mostly unisexual.
Androecium – Stamens 2-20 (in male flowers), often 4; anthers basifixed, dehiscence by vertical slits.
Gynoecium – Carpels 2 (in female flowers); ovary superior, unilocular; ovule 1, orthotropous; style 2-branched.
Fruit – Drupe, covered with a whitish wax secretion.
Position and Affinity of the Family:
The conspicuous peltate resinous glands of the leaves of the Myricaceae are homologous to similar glands in the Juglandaceae and Fagaceae. Cronquist (1968) commented thus: “The Myricaceae appear to be allied to both the Fagales and Juglandales, but they would be peripheral and aberrant in either order. At the present state of our knowledge it seems most useful to maintain the Myricaceae in an order of their own.”
Number in and Distribution of the Family:
This is a small family of two genera and 35 species, being distributed in the subtropical and temperate regions.
Commonly occurring Plant of the Family:
Myrica esculenta Buch-Ham. ex D. Don, an evergreen dioecious tree with pubescent branchlets, is found in Khasi Hills, Meghalaya.
Economic Aspects of the Family:
The berries of M. cerifera and M. pennsylvanica are the source of an aromatic wax, used for candle and soap. The fruits of M. esculenta are edible. M. gale yields tannic acid.
Family # 2. Ulmaceae (Elm):
General Features of the Family
Habit – Shrubs or trees; sap not milky.
Leaves – Alternate, petiolate, stipulate, unequal sided.
Inflorescence – Cymose, fasciculate or solitary.
Flowers – Bisexual or unisexual.
Perianth – Present, of 4-8 sepaloid segments, somewhat united.
Androecium – Stamens equal in number and opposite to perianth segments; filaments erect in bud; anthers 2-celled, opening by longitudinal slits.
Gynoecium – Carpels 2; ovary superior, unilocular; ovule amphitropous or anatropous, pendulous from apex of ovarian chamber.
Fruit – Drupe or samara.
Seeds – Embryo straight; cotyledons conduplicate, flat or sinuous; endosperm little or none.
Divisions of the Family:
The Ulmaceae is separated into two tribes, according to the nature of fruit and seed:
Tribe (i) Celtideae:
Fruit a reduced drupe. Embryo curved with folded or rolled cotyledons.
Endosperm sometimes present. Examples- Celtis, Trema, etc.
Tribe (ii) Ulmeae:
Fruit a winged nut. Embryo straight with flat cotyledons. Endosperm absent. Examples- Haloptelea, Ulmus, etc.
Number in and Distribution of the Family:
A family of 16 genera and about 2,000 species, the Ulmaceae extends its sway throughout the tropical and extra tropical regions of the world.
Commonly occurring Plants of the Family:
Celtis tetrandra Roxb. and Haloptelea integrifolia (Roxb.) Planch are trees.
Charcoal Tree or Indian Nettle Tree [Trema orientalis (L.) Bl.] is a small twiggy tree, marked with scars.
Economic Aspects of the Family:
The Ulmaceae is important from the economic stand point. Celtis australis, C. occidentalis, C. procera and Ulmus thomasi produce timber. Some species of Celtis are appreciated for their edible fruits. The fragrant wood of Planera abelicea is used as a substitute for sandal wood.
The wood of Trema orientalis is useful in making charcoal for gunpowder; the fruits of this plant are edible. Several species are cultivated domestically as ornamentals, e.g., U. americana, U. carpinifolia, U. glabra, etc. U. rubra yields mucilaginous inner bark, which finds application in the manufacture of medicinal troches. The wood of Zelkova serrata (Japan) is used for making elegant carved boxes.
Family # 3. Cannabinaceae (Hem):
General Features of the Family:
Habit – Herbs, climbing or erect, with no milky sap, aromatic.
Leaves – Alternate or opposite, simple, palmate or palminerved, stipulate.
Inflorescence – Male flowers in paniculate racemes and females in spikes.
Flowers – Apetalous, axillary.
Fruit – Achene, surrounded by a persistent perianth.
Number in and Distribution of the Family:
The Cannabinaceae is a very small family with two genera and three species, out of which Cannabis is tropical and Humulus extends to the north temperate region.
Economic Aspects of the Family:
The leaves of Cannabis sativa are used for making the intoxicating beverage called ‘bhang’ or ‘siddhi’, the resinous exudation is smoked as ‘charas’; the young inflorescences are smoked as ‘ganja’; the seed oil serves as a luminant and in the preparation of paints, varnishes and soap; the bark yields ‘hemp’ which is in demand for cables, tarpaulins, etc.
Hops (Humulus lupulus) are widely cultivated in Europe for the spikes which are used to give flavour and sparkle to beer.
Family # 4. Balanophoraceae (Balanophora):
The family represents non-green total parasites. The vegetative organs are reduced to branched tuberous reddish or yellowish rhizomes which are fixed by means of suckers to the roots of a host tree. Sometimes within the rhizome, the inflorescence develops and then projects above the ground.
The flowers are minute and unisexual, the male being with 3-4 stamens and the female with 1-3 carpels. The inferior ovary contains 1-3 ovules which are naked, sometimes reduced to an embryosac and often united with the ovarian wall. The fruit is a nut. The seed contains abundant endosperm which encloses an undifferentiated embryo.
The Balanophoraceae is akin to the Cynomoriaceae with which it is often merged. Since these plants are notable for their reduced structure and curious development, it is hard to reconcile with the view that they are end products of convergent evolution or they represent natural assemblage.
Although they have links with the Hydnoraceae and Rafflesiaceae, they are probably unrelated to other parasitic groups. They are related to the Olacaceae, Opiliaceae and Santalaceae. A “true relationship, albeit a distant one, may be with Gunnera (Haloragaceae)”.
In the Balanophoraceae, there are 18 genera and 120 species which are prevalent in the savannahs and tropical woods.
Balanophora dioica R.Br, is found in Khasi Hills, Meghalaya.
In Java, waxes are extracted from the plants of the Balanophoraceae and are burnt for lighting. Sometimes the plants are reported to have aphrodisiac properties.
Family # 5. Aristolochiaceae (Birthwort):
General Features of the Family:
Habit – Low herbs or climbing shrubs.
Stem – Softly woody, with broad medullary rays.
Leaves – Alternate, petiolate, simple, entire, exstipulate.
Inflorescence – Racemose or solitary.
Flowers – Bisexual, irregular or regular.
Perianth – Petaloid, enlarged to form a bell-like or trumpet-like structure, usually highly coloured.
Androecium – Stamens 6-36, set around apex of ovary or stylar column; anthers free or united, dehiscing longitudinally.
Gynoecium – Carpels 4-6: ovary inferior, ovules many in each loculus.
Fruit – Capsule, dehiscing septicidally.
Seeds – Embryo small; endosperm fleshy.
Divisions of the Family:
The Aristolochiaceae is divided into three tribes:
Tribe (i) Aristolochieae:
Perennial herbs or shrubs. Flowers irregular, solitary or in cymes or racemes. Petals absent. Stamens in one row, united with style. Ovary inferior. Fruit a capsule. Examples- Aristolochia, Euglypha and Helostylis.
Tribe (ii) Bragantieae:
Shrubs or semishrubs. Flowers regular in cymes or racemes. Petals absent. Stamens in one or two rows, free or united with style. Ovary inferior. Fruit a capsule. Examples- Apana and Thottea.
Tribe (iii) Sarumeae:
Perennial herbs. Flowers regular, solitary. Petals present or absent. Stamens in two rows, free or united at base of filaments. Ovary inferior or semi-inferior. Fruit a capsule or follicle. Examples- Asarum and Saruma.
Number in and Distribution of the Family:
Seven genera and about 625 species constitute the Aristolochiaceae which is distributed throughout the hot and temperate zones of the world.
Commonly occurring Plants of the Family:
Aristolochia bracteolata Lamk. is a decumbent slender perennial. A. tagala Cham, is a twining perennial shrub.
Economic Aspects of the Family:
The family is of some economic importance for ornamentals, e.g., Aristolochia clematitis, A. gigas, A. grandiflora, A. macrophylla, A. orninthocephala and Asarum europaeum. The roots of Aristolochia indica are used by snake charmers for catching snakes. The roots of A. serpentaria and Bragantia wallichii serve as a cure for snake bites.
Family # 6. Hydnoraceae (Hydnora):
This is a small family of herbs, parasitic on the roots of various shrubs and trees. The scale leaves are absent. The flowers are solitary, subsessile, bisexual and rather large. The perianth is very thick. The ovary is inferior and Unilocular; the ovules are very numerous from apical or parietal placetae. The fruit is baccate. The seeds are minute and countless; the endosperm is copious.
The family contains only two genera—Hydnora with about eight species in Africa and the Malagasy Islands and Prosopanche with one species in the Pampas of Argentina.
Family # 7. Rafflesiaceae (Rafflesia):
This is a family of parasitic herbs. The vegetative organs are reduced to mycelia which ramify through the tissues of the host. Produced above the ground as adventitious shoots from the mycelium, the flowers are unisexual, regular and minute to very large.
The perianth is 4- to 5-parted; the male flowers have many stamens and the female 4, 6 or 8 carpels, with an inferior ovary; the ovules are numerous on parietal placentae. The fruit is a succulent berry. The seeds are minute with a hard testa, undifferentiated embryo and oily endosperm.
The Rafflesiaceae is divided into four tribes:
Tribe (i) Apodantheae:
Flowers unisexual, solitary, small. Stamens in 2 or 4 rings on central column. Ovary inferior with 4 placentae or 1 continuous placenta. Example- Apodanthes.
Tribe (ii) Cytineae:
Flowers unisexual, in racemes. Stamens in 1 ring. Ovary inferior with 8- 14 placentae. Example- Cytinus.
Tribe (iii) Mitrastemoneae:
Flowers bisexual, solitary. Example- Mitrastemon.
Tribe (iv) Rafflesieae:
Flowers unisexual, solitary, large. Stamens in 1 ring. Ovary inferior with many irregular chambers. Example- Rafflesia.
“The closest relatives of the Rafflesiaceae are undoubtedly the Hydnoraceae, which differ in having root-like structures, no bracts below the flowers, bisexual flowers and stamens borne on a column. Some botanists prefer to isolate Mitrastemon as a separate family placed between the Rafflesiaceae and Hydnoraceae. The affinities of this group are very uncertain. Most authorities link the Rafflesiaceae with the Aristolochiaceae because they have a similar perianth, but the evidence for this association is not conclusive”.
The Rafflesiaceae is primarily a subtropical family of about nine genera and 500 species, being found in the Old World.
The flower of Rafflesia arnoldi (Sumatra) is the largest in the Plant Kingdom, measuring a metre in diameter and weighing up to 8 kg.
Family # 8. Nyctaginaceae (Four-O’Clock):
General Features of the Family:
Habit – Herbs, shrubs or trees.
Leaves – Opposite, simple, entire, exstipulate, often in unequal pairs.
Inflorescence – Cymose.
Flowers – Monochlamydeous, regular, hypogynous, involucrate.
Perianth – Petaloid, united, inflated at base, segments 5, plicate.
Androecium – Stamens 8-30, exserted, unequal.
Gynoecium – Carpel 1; ovary superior, unilocular, ovule 1, basal, campylotropous with an inferior micropyle; stigma peltate.
Fruit – Achene, enclosed within perianth base.
Seeds – Erect, albuminous; perisperm mealy: embryo curved or folded’, cotyledons unequal.
Floral Range in the Family:
Although Mirabilis has a biparous cyme, the inflorescence shows a tendency to become uniparous at the upper part on account of one sided suppression of axes. Each bract is leaf-like and coloured, subtending a flower, e.g., Bougainvillea. The bracts may be sepal-like and subtend more than a single flower, as in Oxybaphus. The flowers of Pisonia are unisexual.
Number in and Distribution of the Family:
The Nyctaginaceae embraces about 30 genera and 290 species. The members of this family abound in the warmer parts of the world, but are mainly found in tropical America.
Commonly occurring Plants of the Family:
Boerhaavia diffusa L. is a weed.
Bougainvillea spectabilis Wild. is a garden climber with purple bracts.
Four-O’clock Plant or Marvel-of-Peru (Mirabilis jalapa L.) is an ornamental shrub.
Pisonia aculeata L., a large straggling shrub, is armed with recurved axillary spines.
Economic Aspects of the Family:
Economically, the Nyctaginaceae is of little value except as ornamentals. While Abronia. Bougainvillea and Mirabilis are cultivated for showy flowers, Pisonia aculeata is used for hedges. Boerhavia diffusa is of medicinal importance as a diuretic. The tuberous roots of M. jalapa form the source of a purgative utilised as a substitute for jalap. Extracts of P. aculeata leaves and P. capitata fruits’ are tried on a range of complaints. The leaves of P. alba and P. capitata can be recommended as a vegetable.
Family # 9. Phytolaccaceae (Pokeweed):
General Features of the Family:
Habit – Herbs, shrubs or trees.
Leaves – Alternate, simple, entire, exstipulate, glabrous.
Inflorescence – Cymose or racemose.
Flowers – Small, bisexual, regular.
Perianth – Small, non-petaloid, free or united, segments 4-5, imbricate.
Androecium – Stamens 5-30, inserted on a fleshy disc; anthers 2-celled, dehiscence longitudinal.
Gynoecium – Carpels 1-16, free or united; ovary superior, unilocular; ovule basal, campylotropous.
Fruit – Achene, berry, drupe, schizocarp or utricle.
Seeds – Embryo large, annular; cotyledons half terete or flat and narrow; endosperm copious and mealy.
Floral Range in the Family:
The flowers are invariably hypogynous, but epigynous in Agdestis. They are usually actinomorphic, but zygomorphic in Anisomeria.
The stamens form a whorl, the members of which are opposite to (Microtea) or alternate with (Rivina) the perianth segments. There may be two alternating whorls of stamens, the number of which may increase in either of the whorls (Phytolacca decandra, P. icosandra). Sometimes the outer whorl of stamens is replaced by a whorl of 5 petals (Stegnosperma).
The ovary is superior, except in Agdestis where it is inferior.
Divisions of the Family:
The Phytolaccaceae is divided into five tribes:
Tribe (i) Agdestideae:
Ovary inferior. Example- Agdestis.
Tribe (ii) Barbeuieae:
Ovary bicarpellate. Example- Barbeuia.
Tribe (iii) Euphytolacceae:
Ovary multicarpellate. Example- Phytolacca.
Tribe (iv) Rivineae:
Ovary unicarpellate. Example- Rivina.
Tribe (v) Stegnospermaeae:
Staminodes petaloid. Example- Stegnosperma.
Number in and Distribution of the Family:
The Phytolaccaceae comprises 22 genera and 125 species, being widely distributed in tropical America and the West Indies.
Commonly occurring Plants of the Family:
Petiveria alliacea L. is an erect herb with greenish flowers.
Rouge Plant or Bloodberry (Rivina humilis L.) is a semiclimbing undershrub, having showy scarlet berries.
Economic Aspects of the Family:
The Phytolaccaceae is of little economic importance. The species of Agdestis, Ercilla, Petiveria, Phytolacca, Rivina and Trichostigma are grown for ornamental purpose. Petiveria alliacea (South America) is used medicinally. The young shoots of Phytolacca americana form a source of edible greens and berries of this plant yield a deep red dye for colouring wines. A red dye is also extracted from the berries of R. humilis.
Family # 10. Aizoaceae (Carpetweed):
General Features of the Family:
Habit – Herbs or shrubs.
Leaves – Alternate, opposite or whorled, fleshy or thread-like.
Flowers – Bisexual, regular.
Perianth – Uniseriate, 5- to 8-lobed, free or united.
Androecium – Stamens 3-5 or many, outermost forming petaloid structures; anthers 2-celled; dehiscing longitudinally.
Gynoecium – Carpels 3-5; ovary inferior or superior, 2- to many locular, placentation apical, axile or basal.
Fruit – Capsule.
Divisions of the Family:
The Aizoaceae is subdivided on the basis of the characters of the perianth and relative position of the ovary:
Subfamily I Ficoideae:
Perianth segments united to form a shorter or longer tube.
Tribe (i) Aizoaeae:
Staminodes absent. Ovary inferior. Capsule loculicidal. Example- Aizoon.
Tribe (ii) Mesembryanthemeae:
Staminodes numerous or absent. Examples- Mesembryanthemum and Tetragona.
Tribe (iii) Sesuvieae:
Staminodes absent. Ovary superior. Capsule opening by a lid. Examples- Sesuvium and Trianthema.
Subfamily II Molluginoideae:
Perianth segments almost free. Petaloid staminodes generally absent. Ovary superior. Example- Glinus.
Number in and Distribution of the Family:
The Aizoaceae includes 143 genera and about 2,300 species. The members of this family are highly developed in South Africa.
Commonly occurring Plants of the Family:
Glinus lotoides (O. Kuntze) L. is a prostrate herb.
Trianthema portulacastrum L. is a creeping herb on the seashore.
Economic Aspects of the Family:
Economically, the Aizoaceae is of little significance. The species of Mesembryanthemum are suitable for cool green houses. The fruits of M. acinaciforme and M. edule (South Africa), called ‘Hottentot figs’, are edible. Tetragonia tetragonioides (New Zealand) is a source of edible greens.
Family # 11. Basellaceae (Basella):
General Features of the Family:
Habit – Climbing herbs, often succulent.
Leaves – Alternate, petiolate, simple, exstipulate.
Inflorescence – Panicles, racemes or spikes.
Flowers – Apetalous, bisexual, regular, often brightly coloured.
Perianth – Uniseriate, free or united into a 5-lobed structure persistent.
Androecium – Stamens 5; filaments short; anthers 2-celled, dehiscing lengthwise.
Gynoecium – Carpel 1; ovary superior, unilocular; ovule 1, campylotropous; placentation basal.
Fruit – Drupe, enveloped by a persistent perianth.
Seeds – Spherical, with a membranous testa; embryo semiannular or twisted; endosperm copious.
Floral Range in the Family:
The stamens are curved in bud (Anredera) or straight in bud (Basella).
Position and Affinity of the Family:
While Rendle was silent about the Basellaceae, it was mentioned by Lawrence, Core and Hutchinson. It was united with the Chenopodiaceae by Bentham-Hooker. It is probably an advanced terminal offshoot of the Portulacaceae.
Number in and Distribution of the Family:
The Basellaceae is composed of four genera and 22 species, being found in tropical Africa, Asia and America.
Commonly occurring Plant of the Family:
Basella alba L. is a much branched fleshy twining herb.
Economic Aspects of the Family:
Basella alba and B. rubra produce edible shoots. Boussingaultia gracilis (tropical America) is cultivated as an ornamental for fragrant white flowers as well as for edible tubers. The tuberous starchy roots of Ullucus tuberosus (Andes) are used as a substitute for potatoes.
Family # 12. Portulacaceae (Purslane):
General Features of the Family:
Habit – Herbs or undershrubs.
Leaves – Alternate or opposite, simple, succulent with scarious stipules.
Inflorescence – Cymose.
Flowers – Bisexual, regular, hypogynous without a disc.
Calyx – Sepals 2, imbricate.
Corolla – Petals 4 or 5, free.
Androecium – Stamens 4 or more, opposite to petals and united with them at base.
Gynoecium – Carpels 3, syncarpous; ovary semi-inferior, 1-celled, containing several campylotropous ovules on basal central placenta.
Fruit – Capsule with a circumscissile or loculicidal dehiscence.
Position and Affinity of the Family:
Bentham – Hooker included the Portulacaceae in the Caryophyllales.
Rendle placed it under the Centrospermae and Lawrence did like-wise.
Like the Caryophyllaceae, the Portulacaeae has come from the same source—the Phytolacceaeae.
The floral type of Portulaca evolved by the disappearance of the inner whorl of carpels and by the juxtaposition of a pair of bracteoles to the flower to form the dimerous calyx.
The Portullacaceae shows close relationship with the Basellaceae, as the genera Portulacaria and Phillippiamra stand intermediate betplants belonging to this family are somewhat cosmopolitan, between the two families. It is also related to the Aizoaceae, but botanists do not agree with regard to the placement of some of the genera.
Number in and Distribution of the Family:
There are 19 genera and about 500 species in the Portulacaceae. The plants belonging to this family are somewhat cosmopolitan, but there is one principal centre of distribution in South America and another in the western part of the United States.
Common occurring Plants of the Family:
Rose Moss or Sun Plant (Portulaca grandiflora Hook.) is a garden annual with showy red coloured flowers and sensitive stamens.
Purslane (Portulaca oleracea L., P. quadrifida L., P. tuberosa Roxb.), having golden-yellow flowers, are weed in waste places.
Economic Aspects of the Family:
Many garden varieties of Calandrinici, Ceraria, Claytonia, Lewisia, Portulaca and Talinum are cultivated. The herbage of P. oleracea is used as a green salad.
Family # 13. Caryophyllaceae (Pink):
General Features of the Family:
Habit – Herbs, having stems with swollen nodes.
Leaves – Opposite, simple, entire, exstipulate.
Inflorescence – Dichotomous cyme.
Flowers – Bisexual, regular, hypogynous or perigynous.
Calyx – Sepals 4 or 5, free, or united.
Corolla – Petals 4 or 5, free, clawed.
Androecium – Stamens 8-10, in 2 whorls, free.
Gynoecium – Carpels 2-5, syncarpous; ovary unilocular, ovules many, amphitropous or campylotropous; placentation free central.
Fruit – Capsule.
Seeds – Somewhat flattened, albuminous; embryo curved.
Floral Range in the Family:
The flowers vary widely. A typical flower is pentamerous, as in Spergula. Sometimes the flowers are tetramerous (Sagina). In Stellaria, the flower is pentamerous with the carpels reduced to three. In one and the same species, we may find considerable variation; a case in point is Stellaria media. Here the flower may have the formula S5 P5+5 A5 G(3) or S5 P5 A5 G(3).
The sepals are free or may be united into a tube. The petals, may be shorter than the sepals and sometimes totally wanting. They are often red in colour and differentiated into a limb and a claw. At the junction of the limb and claw or the corolla throat, there is an outgrowth or a ligule which constitutes the so called corona.
The corona is absent in Githago and Gypsophila, but present in Dianthus, Lychnis and Silene. An internode is also formed above the calyx on which petals, stamens and carpels are borne. In Alsine, Arenaria, Holosteum and others, the petals are more or less notched.
The stamens and carpels differ with regard to their number and arrangement. The inner whorl of stamens is generally absent in Cerastium. In some genera, the stamens are slightly perigynous. The styles are united below in Polycarpon or are free in Dianthus. The carpels are 2 in Saponaria, 3 in Silene and 5 in Lychnis.
Divisions of the Family:
The Caryophyllaceae is divided into three subfamilies:
Subfamily I Alsinoideae:
Sepals distinct. Petals present. Fruit a capsule. Examples- Arenaria, Cerastium, etc.
Subfamily II Paronychioideae:
Sepals distinct or united. Petals absent. Fruit a utricle.
Examples- Paronychia, Scleranthus, etc.
Subfamily III Silenoideae:
Sepals united. Petals present. Fruit a capsule. Examples- Dianthus, Lychnis, etc.
Position and Affinity of the Family:
According to Engler, the Caryophyllaceae is the most advanced family under the Centrospermae. Rendle suggested it to be a connecting link between the Monochlamydeae and Dialypetalae. Hutchinson placed the family in the Caryophyllales.
The ultimate basis of affinity of the Caryophyllaceae lies in its origin. According to one school of thought, the family has come from the Phytolaccaceae by the evolution of petals from the outer whorl of stamens and by the evolution of stamens from the whorl outer of carpels. Others have claimed that the Caryophyllaceae has been derived from the Ranales, giving rise to reduced taxa, such as the Amaranthaceae and Chenopodiaceae. Still some have considered the family as the ancestor of the Primulaceae.
The Caryophyllaceae is related to the Portulacaceae and Geraniaceae. The presence of unilocular ovary with free central placentation is suggestive of the Portulacaceae, while the Caryophyllaceae stands close to the Geraniaceae on account of the pentamerous flowers and nature of stamens.
Number in and Distribution of the Family:
The Caryophyllaceae represents about 80 genera and about 2,000 species. The family is primarily available in the north temperate regions, but also distributed in the south temperate lands and tropical mountains; the Mediterranean area is the main centre of distribution.
Commonly occurring Plants of the Family:
Sweet William (Dianthus barbatus L.), Carnation (D. chinensis L.), Baby’s Breath (Gypsophila paniculata L.) and G. elegans Bieb. are season flowers.
Drymaria cordata Willd. and Spergula arvensis L. are weeds in cool climates like those of Darjeeling and Shillong.
Polycarpaea corymbosa (L.) Lamk., Chickweed [Stellaria media (L.) Vill.] and Cowcockle [Vaccaria pyramidata (L.) Medik] are herbaceous plants, generally considered as weeds.
Economic Aspects of the Family:
Economically, the plants of the Caryophyllaceae are of little or no importance. They are generally unpalatable to livestock. Spergula arvensis var. sativa is occasionally used as a fodder plant in dry sandy areas. Some are used as vegetables, e.g., Polycarpon prostratum. Others are chiefly valuable for their flowers, such as the species of Agrostemma, Cerastium, Dianthus, Gypsophila, Lychnis, Saponaria and Silene. The roots of Vaccaria pyramidata yield ‘saponin’ which forms lather with water.
Family # 14. Ceratophyllaceae (Hornwort)
The family comprises one genus (Ceratophyllum) and two or about 30 species of cosmopolitan distribution.
Ceratophyllum demersum L., a fragile herb, is seen in slow moving or shallow stagnant water, “Ceratophyllum usually floats in mats just below the surface of water. These mats provide a valuable protection for fish fry but also provide protection for bilharzia carrying snails and malaria or filaria carrying mosquito larvae”.
Family # 15. Monimiaceae (Monimia):
The family is distinguished by the monoecious or dioecious plants, exstipulate leaves, valvular dehiscent anthers, achene fruit and copious endosperm.
The Monimiaceae is of great phyletic significance, because it is a combination of magnoliaceous and lauraceous characters. The floral plan is suggestive of the Magnoliaceae with a concave axis in which many stamens and free carpels are depressed. The small embryo embedded in a copious endosperm also speaks for an alliance with the Magnoliaceae.
A relationship is indicated with the Lauraceae in terms of perigynous flowers as well as valvular dehiscent anthers and appendaged filaments. The Monimiaceae approaches the Calycanthaceae with regard to the hollowed out receptacle. Rosalian affinities are expressed by apetaly and somewhat urceolate receptacle with valvate stamens. But the biological feature of the flowers, namely the inconspicuous and generally unisexual flowers, is very peculiar to the Monimiaceae.
In the Monimiaceae, there are 30 genera and about 450 species. The members of this family abound in southern hemisphere, especially in Malagasy, Polynesia, Oceania and Australia.
The wood of Atherosperma moschatum and Doryphora sassafras, both of Australia, is used for making furniture. Laurelia aromatica (Peru) yields a type of spice called ‘Peruvian nutmeg’, novae- zelandiae (New Zealand) yields valuable timber. Peumus boldus (Chile) provides edible fruit as well as wood for cabinet work.
Family # 16. Myristicaceae (Nutmeg):
The family is featured by the pellucid dotted leaves, unisexual flowers, monadelphous stamens, arillate seeds and ruminate endosperm.
The Myristicaceae is a taxon of about 16 genera and 380 species, being distributed in the tropical regions of the world and inhabiting lowland rainforests.
Gymnacranthera farquhariana and Virola surinamensis possess waxy seeds, utilised as a source of butter for candle making and human consumption. Myristica fragrans is the source of ‘mace’ obtained from the dried aril and of ‘nutmeg’ from the seed. The pericarp of the fruit is also used to make a jelly preserve and inferior seeds are pressed to make nutmeg butter used in perfumery.
Family # 17. Lauraceae (Laurel):
General Features of the Family:
Habit – Shrubs or trees, with an aromatic bark.
Leaves – Alternate or opposite, simple, entire, exstipulate.
Inflorescence – Panicles, racemes, spikes or umbels.
Flowers – Bisexual or unisexual, regular.
Perianth – Small, undifferentiated, biseriate, of 6 basally connate segments.
Androecium – Stamens in 4 whorls of 3 each, innermost reduced to staminodes; anthers 2- or 4- celled, basifixed; dehiscing by flap-like valves.
Gynoecium – Carpel 1, ovary superior, unilocular; ovule solitary pendulous, anatropous.
Fruit – Berry or drupe, surrounded by persistent perianth base seated upon an enlarged receptacle.
Seeds – Embryo straight; endosperm absent.
Divisions of the Family:
The Lauraceae is divided into two subfamilies:
Subfamily I Lauroideae:
Anthers 4-celled. Examples- Cinnamomum, Laurus, etc.
Subfamily II Perseoideae:
Anthers 2-celled. Examples- Cassytha, Persea, etc.
Number in and Distribution of the Family:
The Lauraceae represents about 32 genera and 2,500 species, being prevalent in the tropical and subtropical regions of both hemispheres. The chief centres of distribution include Brazil and South-east Asia.
Commonly occurring Plants of the Family:
Cassytha filiformis L. is a thread-like, leafless and greenish parasite.
Cryptocarya floribunda Nees, Dehaasia kurzii King, Machilus villosa Hook. f. and Phoebe lanceolata (Nees) Nees are trees.
Economic Aspects of the Family:
In an economic sense, the plants of the Lauraceae are important for aromatic oils, edible fruits and useful timber. Aniba panurensis (Guyana) and A. rosaeodora var. amazonica (Brazil) yield ‘bois de rose’, a perfume. Cinnamomum burmanni (Indonesia), C. cassia (Burma), C. massoia (New Guinea), C. oliveri (Australia) and C. tamala furnish ‘cassia bark’, used for flavouring purposes.
Camphor is obtained by distillation of the wood of C. camphora, C. loureirii (Vietnam) and C. zeylanicum are cultivated for their aromatic bark called ‘Saigon cinnamomum’ and ‘cinnamomum’ respectively. Beilschmiedia roxburghiana, C. cecidodaphne, Nectandra rodiaei (Guyana), Ocotea bullata (South Africa), Persea nammu (China) and Umbellularia California (USA) produce valuable timber. P. gratissima (tropical America) is the source of edible fruits termed ‘alligator pear’ or ‘avocado’. The leaves of Laurus nobilis (Europe) from ‘sweet bay’, much used in cooking. The root-bark of Sassafras albidum (eastern North America) constitutes ‘oil of sassafras’, a flavouring material.
Family # 18. Berberidaceae (Berberry):
General Features of the Family:
Habit – Herbs or shrubs.
Leaves – Alternate or basal, simple or compound, exstipulate.
Flowers – Bisexual, regular, hypogynous.
Perianth – Biseriate, segments free and distinct.
Androecium – Stamens 4-18, in 2 whorls; anthers 2-celled, opening by flap-like valves.
Gynoecium – Carpel 7; ovary superior; ovules many or few.
Fruit – Berry or follicle.
Seeds – Embryo straight; endosperm copious.
Divisions of the Family:
The Berberidaceae is divided into two subfamilies:
Subfamily I. Berberidoideae:
Foliage leaves simple or compound Flowers with honey leaves.
Examples- Berberis, Leontice, Mahonia, etc.
Subfamily II. Podophylioideae:
Foliage leaves not pinnately divided. Flowers without honey leaves. Examples- Achlys, Podophyllum, etc.
Number in and Distribution of the Family:
The Berberidaceae is represented by 13 genera and 550-600 species, chiefly distributed in the temperate zones of northern hemisphere from Central Asia to India as well as from the Andes to the Straits of Magellan.
Commonly occurring Plants of the Family:
Berberis asiatica Roxb. ex DC., B. insignis Hook. f. & Thorns, and B. lycium Royle are shrubs.
Mahonia leschenaultii (Wall, ex Wt.) Takeda is known from Western Ghats to the Nilgiris southwards.
Podophyllum hexandrum Royle is found in western Himalaya at an altitude of 1,843 – 4,267 m.
Economic Aspects of the Family:
The Berberidaceae is of importance for ornamentals, e.g., Berberis buxifolia, B. calliantha, B. thunbergii, Mahonia aquifolium, M. bealei, M. lomariifolia and Nandina domestica. B. vulgaris is known as the obligate host of the aecidial stage of wheat rust. The rhizome of Podophyllum peltatum is the source of the drug ‘podophyllin’.
Family # 19. Menispermaceae (Moonseed):
The family is recognised by the lianous habit, unisexual and trimerous flowers, drupaceous fruits and curved seeds.
The family includes 65 genera and roughly 350 species, being distributed in the tropical parts of the world.
Cocculus hirsutus (L.) Diels, Stephania hernandifolia Walp. and Tiliacora acuminata (Lamk.) Miers are climbers. Coscinium fenestration (Gaertn.) Colebr. is found in Western Ghats.
The family is of little economic importance except for ornamentals (Cissampelos, Cocculus and Menispermum). ‘Curare’, chiefly obtained from Chondrodendron tomentosum is utilised as a muscle relaxant in surgical operations. A tonic is prepared from the roots of Jateorhiza palmata. The roots of Tinospora cordifolia serve as a febrifuge.
Family # 20. Lardizabalaceae (Lardizabala):
The family is known by the lianas with digitately compound leaves, perulate flower buds, stamens opening lengthwise and baccate fruit.
A family of nine genera and 36 species, the Lardizabalaceae is found in the Himalaya, China, Japan and Chile.
The fruits of all species are edible, particularly Akebia quinata and Decaisneafargesii. Holboellia coriacea is cultivated ornamentally.
Family # 21. Fumariaceae (Fumitory):
General Features of the Family:
Habit – Delicate smooth herbs or climbers, with a watery sap.
Leaves -Alternate, compound, dissected, exstipulate.
Flowers – Bisexual, irregular, hypogynous, perfect.
Calyx – Sepals 2, small, deciduous.
Corolla – Petals 4, in two pairs, somewhat connivent, inner one narrower and coherent and outer basally saccate or spurred.
Androecium – Stamens 4, free and opposite to petals or 6 and united into two bundles.
Gynoecium – Carpels 2; ovary superior, unilocular; placentation parietal.
Fruit – Capsule or nut.
Seeds – Embryo minute; endosperm fleshy.
Position and Affinity of the Family:
Engler, Wettstein and others accepted the Fumariaceae as a subfamily within the Papaveraceae. Hutchinson recognised the Fumariaceae as a separate family, but included the Hypecoideae in it. The zygomorphic flower as well as the androecial situation led Lawrence, Core and Mitra to treat it as a distinct family under the Rhoeadales.
The Fumariaceae stands close to some extent to the monocotyledonous plants due to the presence of a single cotyledon, subterranean tubers and rhizomes bearing scales in several species of Corydalis and Dicentra.
Number in and Distribution of the Family:
The Fumariaceae contains 16 genera and about 450 species, distributed mainly in the north temperate regions and especially in the Mediterranean basin.
Commonly occurring Plants of the Family:
Fumaria indica (Haussk.) Pugsly is a small branched annual herb in waste places.
Economic Aspects of the Family:
Economically, the Fumariaceae is of little importance except for ornamentals. Corydalis ramosa is useful in the treatment of eye diseases. The pea-like tubers of Dicentra canadensis form ‘corydalis’ of commerce.
Family # 22. Resedaceae (Mignonette):
The family is characterised by the glandular stipules, zygomorphic flowers, laciniate petals, open unilocular ovary and capsule with an apical dehiscence.
According to Engler, Bessey and Rendle, the Resedaceae is a phyletically advanced taxon within the Rhoeadales. Following the procedure of Bentham-Hooker, Hutchinson aligned the family with the Violaceae.
The family is most closely allied to the Capparidaceae; this is evident by the xerophytic habit, zygomorphic flower, gynophore development and parietel placentation. An additional link between the two families is the presence of a third and innermost seed coat in species of both Capparidaceae and Resedaceae. However, the remarkable tetramery of the capparidean flower is absent in the Resedaceae.
The Resedaceae comprises six genera and about 75 species, being developed mainly in the Mediterranean basin and South Africa.
The family is of little economic value. Reseda luteola was once used as a source of ‘weld’, a reddish yellow dye for textile industry. R. odorata is grown for fragrant flowers and yields a perfume oil.
Family # 23. Moringaceae (Moringa):
The family is distinguihsed by the alternate pinnately compound leaves, zygomorphic flowers having five stamens and three to five alternating staminodes on a short hypanthium as well as a trivalved elongated fruit with winged seeds.
The position of the Moringaeceae is within the Rhoeadales, as treated by Bessey, Wettstein and Core. Rendle ignored the family. Hutchinson included the family in the Capparidales along with the Capparidaceae and Tovariaceae. Puri (1942) considered the family as distinguished by its complicated gynoecial condition which is also known in the Capparidaceae and Cruciferde.
Datta and Mitra (1947) claimed the Moringaceae as most closely allied to the Violaceae. The zygomorphic flower of the Moringaceae having the perianth and stamens borne on a hypanthium, furnishes a link with the Rosaceae.
The family contains one genus Moringa and 12 species. It “has a distribution from the Mediterranean and North Africa to the Arabian peninsula and India, and is also represented in southwestern Africa and Madagascar”.
The family is of economic importance for the Horse radish Tree (Moringa oleifera), producing fruits. The seeds ‘yield’ ‘oil of ben’, a non-drying oil, which finds application in the lubrication of watches. The roots serve as the source of a condiment.
Engler, Rendle, Lawrence and Core considered the three families as forming a natural group, Bentham-Hooker placed the Sarraceniales under the Parietales, the Droseraceae under the Rosales and the Nepenthaceae under the Multiovulate Terrestres. Hallier reduced the Nepenthaceae to the status of a tribe under the Sarraceniaceae.
Diels treated the Droseraceae as a component of the Parietales, having an affinity with the Violaceae. Hutchinson shifted the Nepenthaceae to the Aristolochiales, keeping the Sarraceniaceae and Droseraceae within the Sarraceniales. The Droseraceae and Nepenthaceae have very similar pollen in addition to the obvious exomorphic characters.
“The group”, in the words of Porter (1967), “represents an early modification, and a terminal one, from the Ranales by specialization of the leaves and the adoption of a specialized habitat”. Despite the admitted differences between the three families, the insect-catching leaves are homologous in all of them.
“The insectivorous habit of the Sarraceniales may be presumed to be an evolutionary response to their growth in habitats deficient in available nitrogen. The Sarraceniaceae and Droseraceae commonly grow in water logged soils containing little or no soluble nitrate. The Nepenthaceae occur in wet, tropical forests, which characteristically have nutrient-poor soils. Many other groups of plants have faced similar problems, but very few have learned to meet them by trapping insects”.
Family # 24. Droseraceae (Sundew):
This is a small family of four genera and about 83 species. Drosera and Drosophyllum are nicknamed as the bird-lime or fly-traps of the Plant Kingdom. While Drosera is an active trap, Drosophyllum is a passive one.
Drosera is available on all continents, but mainly in Australia. It is found in abundance in the wastelands fringing upon the road from Giridih to Parashnath Hills, Jharkhand. Each plant is in possession of a rosette of orbicular or spathulate reddish leaves which are studded with glandular leaves called tentacles. From a distance, the leaves wear the look of a circular red spot; it may seem that the spot has been caused by the spittle of a man chewing Betel leaves.
“Each hair secretes a drop of fluid which shines so bright in the sun that insects are induced to alight upon it in the hope of getting a sip of water. The fluid, however, is so sticky that the unfortunate insects cannot get away from it. Every effort they make puts the hope of escape further and further away; for gradually the hairs collect, bend over and take a firm hold of them. The insects caught by this trap soon lose their strength and die, and are decomposed and absorbed”.
Drosophyllum ranges from Morocco to Portugal and South Spain. In the plant, we notice a short woody stem which passes above into the branched cymose inflorescence. The leaves are long and narrow, being crowded on the upper portion of the stem and branches. “One of the species … is used in rural districts of Portugal as a substitute for fly paper. The plants are hung in doorways, and by means of their sticky leaf secretions, firmly hold insects which alight on them”.
Dionaea is strictly endemic to the coastal plains of North and South Carolina, USA. The leaf- blade is similar to a steel-trap which is itself an active device. The upper red surface bears six sensitive hairs or triggers. As stimulation is initiated by the movement of an insect, the leaf tends to close abruptly. After 5-10 days, digestion and absorption are complete.
Aldrovanda is widely distributed. It is also prevalent in the saltmarshes south of Calcutta and in the Sunderbans area. It is a modified version of Dionaea, as the insect catching mechanism is the same in both. There is an obvious difference: the pointed hairs are numerous in Aldrovanda and six in Dionaea. Also, the former floats in water and has whorls of leaves.
Roridula has leaves like Drosera, without any movement of the tentacles. The former is confined to South Africa. It was once regarded as carnivorous, but has been shown by Lloyd (1942) not to be so. Here the secretion of glands is resinous and not digestive.
Family # 25. Sarraceniaceae (Pitcher-Plant):
The family is represented by three genera and 17 species. They have limited distribution—Darlingtonia in northern California and southern Oregon; Heliamphora in Guyana and Venezuela; Sarracenia in eastern and north-eastern North America. These genera are linkened to the pitfalls of the Plant Kingdom. Pitfalls are passive traps.
Family # 26. Nepenthaceae (Nepenthes):
The family contains one genus (Nepenthes) and about 70 species, inhabiting the tropics of the Old World from China to Australia with the greatest development in Jaintia and Garo Hills of Meghalaya.
Nepenthes conforms to the pitfall type of trap. Here the pitcher is a remarkably intricate device. It attracts insect by virtue of colour or odour and contains a copious amount of liquid (made up of rainwater and dew as well as secreted enzymes and acid). Inside the pitcher, there are a number of downward-pointing stiff hairs which make a precarious foothold.
When insects wander around the leaf, they crawl into the pitcher, lose their footing and get drowned in the liquid. Following the death of the insects, their bodies are digested and absorbed by the leaf cells. In contrast with other carnivorous plants, the pitcher plants do not move in consonant with their catch. Moreover, the effectiveness of the insect traps are manifested by the presence of a mass of undigested exoskeletons generally to be noticed in any mature leaf.
The stems of Nepenthes distillatoria (Sri Lanka) and N. reinwardtiana (Malaysia.) are used as a kind of cordage as well as for making baskets.
Family # 27. Crassulaceae (Orpine):
The family is distinguished by the succulent character of stems and leaves, stamens and carpels as many as petals and pistil with a scaly gland at the base.
The Crassulaceae shows affinity with the Saxifragaceae (Subramanyam, 1970). Crassula aquatica, which has the most reduced endosperm in the Crassulaceae, has a mode of habit similar to the Podostemonaceae. This taxon forms a connecting link between the two families and supports Maheshwari’s (1945) contention that the Podostemonaceae are much reduced apetalous derivatives of the Crassulaceae.
In the Crassulaceae, there are 35 genera and 1,500 species. The plants of this family are abundant in the arid regions, especially in south-central Asia, Mediterranean area. South Africa, northern Mexico and south-western United States.
Bryophyllum pinnatum (Lamk.) Oken. and Kalanchoe laciniata DC. are fleshy herbs, the former with long tubular pendulous flowers and the latter with erect protandrous flowers.
The members of the family are of importance as ornamentals, such as the species of Aeonium, Echeveria, Rochea, Sedum, etc.
Family # 28. Cunoniaceae (Cunonia):
The family is distinguished by the tree-like habit, opposite or whorled leaves and carpellary margins of each placenta distinct or recurved.
The family comprises 26 genera and 250 species, exclusively distributed in the southern hemisphere and largely in the Oceania and Australasia.
The family is of some importance. The species of Ackama, Callicoma, Ceratopetalum and Weinmannia are of value as ornamentals. Ceratopetalum apetalum (New South Wales) yields timber and Weinmannia pubescens (northern Andes) tannin.
Family # 29. Connaraceae (Connarus):
The family is characterised by the pinnate leaves, free carpels and arillate seeds.
The family is composed of 16 genera and about 350 species, being prevalent in the tropics of both hemispheres.
The leaves of Agelaea emetica (Malagasy) yields an essential oil which promotes vomiting and those of A. villosa (West Africa) are used to treat dysentery. The leaves of Cnestis corniculata and C. ferruginea constitute the source of an astringent and a laxative respectively.
The seeds of Connarus africanus are converted into a flour which is effective as an anthelmintic. C. guianensis (Guyana) yields timber. The bark of Rourea glabra (Central America) is used for tanning animal hide and the roots of the same plant yield a strong fibre for making ropes. The fruits and seeds of R. volubilis are utilised for poisoning dogs.
Family # 30. Saxifragaceae (Saxifrage):
In this family, the leaves are exstipulate, flowers perigynous or epigynous, stamens and carpels few and endosperm abundant.
The family includes 80 genera and about 1,250 species are cosmopolitan in distribution, but found mostly in the north temperate regions.
The family is important for ornamentals, e.g., Astilbe, Bergenia, Deutzia, Escallonia, Hydrangea, Philadelphus, Saxifraga, etc. Some yield edible fruits, e.g., Ribes americanum, European Gooseberry (R. grossularia), R. hirtellum, Black Currant (R. nigrum). Red Currant (R. rubrum) and White Currant (R. sativum).
Family # 31. Pittosporaceae (Pittosporum):
The family is recognised by the coriaceous exstipulate alternate or whorled leaves and by the flowers with short filaments, poricidal anthers, simple style, 2- to-5-cxarpelled ovary ad multiovulate placentae.
A family of nine genera and 200-400 species, the Pittosporaceae is found in the warmer parts of the Old World and is highly developed in Australia.
The family is important for ornamentals, e.g. Pittosporum and Sollya. Pittosporum also yields timber. Billardiera longiflora (Tasmania) is raised for blue edible berries.
Family # 32. Caesalpinioideae:
Commonly occurring Plants of the Subfamily:
Camel’s Foot (Bauhinia acuminata L., B. purpurea L.. B. variegata L.) are trees with deeply emarginate leaves.
Fever Nut (Caesalpinia crista L.) is a hook climber.
Peacock Flower [Caesalpinia pulcherrima (L.) Swartz] is a roadside shrub with crimson flowers. Indian Laburnum (Cassia fistula L.) is a big tree, having long pendulous racemes of yellow flowers and rod shaped legumes.
Cassia occidentalis, L. C. sophera L. and C. tora L. are shrubs on waste lands.
Gold Mohur [Delonix regia (Boj.) Raf.] and Peltophorum pterocarpum (DC.) Backer ex K. Heyne are trees, the former with deep crimson to salmon flowers and the latter with yellow flowers.
Kingiodendron pinnatum (Roxb.) Harms is a small tree.
Parkinsonia aculeata L. is a large shrub.
Economic Aspects of the Subfamily:
The wood of Acrocarpus fraxinifolius is used for furniture, boards, shingles and tea boxes. From the trunks of Bauhinia purpurea, we get the gum called ‘semi-gond’. The bark of B. vahlii yields the fibres termed ‘selu’ which is utilised for making ropes. The pods of Caesalpinia coriaria, C. digyna and C. sappan are used in the tanning of leather.
Valuable resins are obtained from Copaifera mopane (Africa), Hymenaea courbaril (West Indies) and Trachylobium verrucosum (Zanzibar). The microscopic stain, ‘haematoxylin’, comes from the wood of Haematoxylon campechianum. The gum obtained from Kingiodendron pinnatum is valued as a wood preservative.
Cercis angustifolia (Arabia) yields a cathartic. The infusion of the leaves of Cassia auriculata is slightly aromatic and finds use as a substitute for tea. The leaves of C. acutifolia, C. angustifolia and C. obovata, when dried, form the drug ‘senna’. The bark decoction of Saraca indica is used as a remedy for defective menstruation. Tamarindus indica is used for culinary purposes.
Family # 33. Mimosoideae:
Commonly occurring Plants of the Subfamily:
Acacia auriculaeformis A. Cunn. ex Benth. is a tree which bears phyllodes.
Bead Tree or Coral Pea (Adenanthera pavonina L.) is a large deciduous unarmed tree.
Silk Flower [Albizia lebbeck (L.) Benth.] is a road side tree.
Entada phaseoloides (L.) Merr. is a woody climber, having snake-like branches.
Sensitive Plant (Mimosa pudica L.) is a straggling herb.
Neptunia plena (L.) Benth. and N. prostrata (Lamk.) Baill. are aquatic weeds with sensitive leaves.
Manila Tamarind [Pithecellobium dulce (Roxb.) Benth.] is a medium sized tree.
Prosopis chilennis (Molina) Stuntz is a desert shrub.
Rain Tree [Samanea saman (Jacq.) Merr.] is a tree, being planted on road sides.
Economic Aspects of the Family:
A number of trees furnish valuable timber, e.g., Acacia melanoxylon (Australia), A. visco, Albizia lebbeck, A. procera, Enterolobium cyclocarpum (tropical America) and Xylia xylocarpa (Burma). Acacia armata and A. karroo form good sand binders or hedges. The seeds of Adenanthera pavonina are employed as beads for rosaries; the powdered wood of this tree is made into a paste and used by Brahmins for marking their foreheads.
Albizia moluccana and A. chinensis are used as a shade for Tea in India, while Inga edulis is a shade for Coffee in Colombia and Central America. The seeds of Entada phaseoloides are utilised for curling garments. The seeds of Prosopis juliflora are ground up and utilised as an animal feed.
From the wood of Acacia catechu are obtained three articles, namely, ‘cutch’, ‘kath’ and ‘kheersal’. A. decurrens (Australia) and A. dealbata (Australia) are useful in tanning. The flowers of A. farnesiana on distillation, yield the well-known ‘Cassie perfume’. Strong fibres, extracted from the stems of A. leucophloea and A. pennata, are used for making ropes and fishing nets. The trunks of A. nilotica, A. scorpioides and A. Senegal yield ‘gum acacia’, ‘gum ghati’ and ‘gum arabic’ respectively. The pods of A. rugata are in demand as a detergent for washing silk and woolen fabrics.
Family # 34. Papilionoideae:
Commonly occurring Plants of the Subfamily:
Crab’s eye or Indian Liquorice (Abrus precatorius L.) is a perennial wiry climber with pink flowers and usually scarlet seeds having a black end.
Flame-of-the-forest [Butea monosperma (Lamk.) Taub.], Butterfly Pea or Mussel shell Creeper (Clitoria ternatea L.), Rattlewort (Crotolaria sericea L.) and Coral Tree [Erythrina variegata L. var. orientalis (L.) Merr.] are plants with very showy flowers.
Butea parviflora Roxb. is a woody climber.
Sword Bean [Canavalia gladiata (Jacq.) DC.] is a large climber.
Crotalaria retusa L. is a garden plant.
Dalhousiea bracteata Grah. ex Benth. is a scandent shrub.
Telegraph Plant [Desmodium gangeticum (L. ) DC.] is a weed of waste places and is noted for the variation movements of two lateral leaflets of the trifoliate leaves.
Melilotus alba Medik. and M. indica (L.) All are field weeds in the winter season.
Cowage (Mucuna prurita Hook.) is a climber whose pods are covered with stinging hairs.
Ormosia robusta Wt. is an erect tree, having imparipinnate leaves.
Pongamia pinnata (L.) Pierre is a tree, being planted on avenues.
Psophocarpus tetragonolobus (L.) DC. is a slender climber.
Psoralea corylifolia L. is an erect annual.
Pueraria tuberosa (Roxb. ex Willd). DC. is a shrubby climber, having tuberous roots.
Smithia abyssinica (A. Rich) Verde, is a common herb (of Pareshnath Hills, Bihar) where the leaves are sensitive.
Hoary Pea or Wild Indigo [Tephrosia purpurea (L.) Pers.] is found on road sides.
Teramnus labialis Spreng. is a slender twiner.
Uraria rufescens (DC.) Schindl. occurs in dry forest undergrowth.
Economic Aspects of the Subfamily:
The species of Astragalus, Glycyrrhiza, Medicago, Melilotus, Psoralea and others are useful in medicine. Lupinus alba, Sesbania cannabina and others form natural fertiliser. The species of Onobrychis, Trifolium and many others are fodder plants. Ornamentals include the species of Baptisia, Cytisus, Genistea, Wisteria, etc.
Arachis hypogaea is cultivated for the fruits, the seeds of which are eaten and also yield oil. The pulses, such as Pigeon Pea (Cajanus cajan), Gram (Cicer arietinum), Lentil (Lens culinaris), Green Gram (Phaseolus aureus), Black Gram (P. mungo), Pea (Pisum arvense, P. sativum), Lathyrus sativus, Soybean (Glycine max), etc. are important food grains.
The pods of Horse Gram (Dolichos biflorus), Black Bean (D. lablab), Lima Bean (Phaseolus lunatus), Scarlet Runner (P. coccineus), Broad Bean (Vicia faba), and Asparagus Bean (Vigna sinensis) as well as the flowers of Sesbania grandiflora are common table vegetables. Pachyrhizus erosus and Psoralea esculenta have edible tuberous roots. The seeds of Trigonella corniculata are used as a flavouring agent.
The seeds of Abrus precatorius are used by goldsmiths as small weights called ‘ratty’. The pith like stems of Aeschynomene aspera and A. indica are utilised for making shola hats, fishing floats, nets, baskets and rafts. Many trees yield timber, e.g. Baphia nitida (West Africa), Castanospermum australe (Australia), Dalbergia latifolia, D. sissoo, Erythrina caffra (South Africa), Pterocarpus indicus and others. The gum exuding from the bark of Butea monosperma is the so called ‘Bengal kino’.
The main produce of Crotalaria burhia and C. juncea is their fibres, used for making cordage, coarse gunny cloth and canvas. The bark of Erythrina suberosa is suitable for cork plugs and insulation boards. The powdered wood of E. variegata is made into face powder. Dyes like ‘indigo’ and ‘santalin’ are obtained from Indigofera tinctoria and Pterocarpus santalinus respectively. The leaves, flowers and twigs of Genistea tinctoria are the source of a yellow dye used for colouring fabrics. Myroxylon balsamum var. balsamum (Venezuela) and M. pereirae var. pereirae (Peru) produce balsam. Pterocarpus marsupium is the source of the red gum ‘kino’; P. officinalis (Central America) yields a red resin.
Family # 35. Bixaceae (Bixa):
The family is recognised by the reddish sap, palminerved leaves, horseshoe shaped anthers and seeds with a red fleshy testa.
A family of one genus (Bixa) and one or four species, the Bixaceae is found in South America.
An orange dye, ‘annatto’, produced from the seed testa of Bixa orellana, is used to colour butter, cheese and other foods.
Family # 36. Tamaricaceae (Tamarisk):
The family is characterised by the sinuous branchlets, scale-like leaves and hairy seeds.
The family is divided into two tribes:
Tribe (i) Reaumurieae:
Flowers solitary. Seeds with endosperm. Examples- Hololachne and Reaumuria.
Tribe (ii) Tamarisceae:
Flowers borne in spike-like or racemose inflorescence. Seeds without endosperm. Examples- Myricaria and Tamarix.
There are four genera and about 120 species in the Tamaricaceae; these are desert, steppe and sea shore plants of the Mediterranean area and Central Asia.
Tamarix dioica Roxb. and T. troupii Hole are found in the islands and sandy banks of Hooghly, West Bengal.
Several species of Tamarix are important as ornamentals due to their feathery foliage, catkin like inflorescence and pink flowers. T. aphylla, T. dioica and T. troupii are employed as fireweed; the galls borne on these trees are rich in tannin and are used for dyeing. The wood of T. articulata (North Africa) is used for house construction. T. mannifera (Egypt to Afghanistan) yields ‘manna’.
Family # 37. Elatinaceae (Water-Wort):
The family is characterised by the aquatic habit, opposite or whorled leaves, paired stipules, axillary cymose trimerous to tetramerous flowers and axile placentation.
The family contains two genera and about 33 species, being widely distributed throughout the subtropical and temperate regions of both hemispheres.
Bergia capensis L. is a glabrous annual where the stems and branches are pink and translucent.
Bergia suffruticosa is used for cleaning teeth.
Family # 38. Caricaceae (Papaya):
The family is known by the presence of latex, unbranched trunks, terminal crown of leaves, union of petals and double row of stamens.
The Caricaceae was accommodated in the Passifloraceae by Bentham-Hooker; the relationship of the two families can be traced to the characters of ovary, placenta and fruit. Van Tieghem considered the Caricaceae as related to the Cucurbitaceae due to the ovular structure which has two thick integuments and a long persistent nucellus, Hutchinson placed the Caricaceae in the Cucurbitales.
The family comprises four genera and 30 species which abound in tropical America.
Papaw (Carica papaya) is well known for the large edible melon-like fruits—”the melon that grows on a tree”; the latex of the unripe fruits is used to make meat tender when cooking; a medicinal compound, ‘papain’ is obtained from the fruits. C. candicans (Peru), C. chrysophila (Colombia) and C. pentagyna (Ecuador) are cultivated for their edible pericarp or sweet juicy seed envelopes.
C. cundincimarcensis is raised successfully at higher altitudes in the tropics where C. papaya would fail. The fruits of Jacaratia mexicana and Jarilla caudata are eaten in the Andes.
In the Theaceae, we find exstipulate leaves, spiral arrangement of perianth segments, several whorls of numerous stamens and axile placentation.
The Theaceae is divided into two tribes:
Tribe (i) Camellieae:
Anthers mostly versatile. Fruit a loculicidal capsule, rarely a drupe. Embryo straight or radicle bent round. Example- Camellia.
Tribe (ii) Temstroemieae:
Anthers mostly basifixed. Fruit a berry or dry and indehiscent. Embryo horseshoe shaped, rarely almost straight. Example- Eurya.
The Theaceae embraces about 29 genera and 1,100 species. The plants of this family are distributed in the tropical and subtropical parts of the world.
Wild Tea (Camellia kissi Wall.) is found in Assam, Khasi Hills and Eastern Himalaya.
The family provides a good number of ornamentals, e.g., Camellia, Cleyera, Eurya, Franklinia, Gordonia and Stewartia. Camellia sasanqua is the source of ‘tea seed oil’, a non-drying oil. C. sinensis is the Tea plant of commerce. Gordonia lasianthus produces tannin. Haploclathra paniculata yields valuable timber.
Family # 39. Dipterrocarpaceae (Dipterocarp):
General Features of the Family:
Habit — Gigantic trees, with an abundant resin.
Leaves — Alternate, simple, entire, stipulate, pubescent.
Inflorescence — Racemes.
Flowers — Bisexual, regular, hypogynous.
Calyx — Sepals 5, united, persistent.
Androecium — Stamens 5 or more, free or slightly polyadelphous; connective produced.
Gynoecium — Carpels 3, united; ovary superior; trilocular with 2 pendulous ovules in each loculus.
Fruit — Samara.
Seeds — Exalbuminous.
Floral Range in the Family:
Deviations from the normal type of flower are few in the Dipterocarpaceae. In general, the calyx and corolla are pentamerous.
The number of stamens varies from one genus to another. The stamens are 5 in Monoporandra. They may be 15 in three whorls, out of which the outer and inner whorls are antisepalous and the middle antipetalous. e.g., Hopea pierrei. The stamens are also monadelphous, as in H. recopei. Except in a few species of Shore and Stemonocarpus, the connective is prolonged at the tip of anther.
Sometimes the ovary is unilocular with parietal placentae, as in Marquesia. It may be adnate to the calyx tube or sunk in the receptacle (Vatica).
Divisions of the Family:
The Dipterocarpaceae is divided into two subfamilies:
Subfamily I. Dipterocarpoideae:
Androecium without a gynophore; anthers basifixed. Wood with intercellular resin canals and multiseriate rays. Example- Dipterocarpus.
Subfamily II. Monotoideae:
Androecium with a gynophore; anthers dorsifixed. Wood without resin canals and with uniseriate rays. Example- Monotes.
Position and Affinity of the Family:
The Dipterocarpaceae is a family under the Guttiferales of some authors and the Parietales of others. Bentham-Hooker included the genera Ancistrocladus and Luphira in this family, but Gilg transferred them to the Ancistrocladaceae and Ochnaceae respectively. Hence, the Dipterocarpaceae has relationship with these families.
The Dipterocarpaceae agrees with the Magnoliaceae in the possession of large stipules. While the calyx persists in the Dipterocarpaceae, it is definitely not so in the Magnoliaceae. The Dipterocarpaceae resembles the Guttiferae by virtue of the resinous content, but differs from it in having stipules and alternate leaves. The Dipterocarpaceae stands very close to the Theaceae; whereas resin canals are present in some members of the former, they are altogether absent in the latter.
Number in and Distribution of the Family:
The Dipterocarpaceae consists of about 15 genera and 580 species. This is chiefly a tropical family, extending from India to New Guinea and the Philippines.
Commonly occurring Plants of the Family:
Anisoptera scaphula (Roxb.) Pierre, Garjan balsam (Dipterocarpus turbinatus Gaertn. f.), Isauxis lanceaefolia King and Sal Tree (Shorea robusta Gaertn. f.) are huge trees.
Economic Aspects of the Family:
The plants of the Dipterocarpaceae are of great value for resins and timber, while the seeds of some species are meant for human consumption. ‘Damar penak’ is derived from Balanocarpus heimii and Shorea hypochra. ‘Eng oil’ is the product of Dipterocarpus tuberculatus.
The stems of D. turbinatus are exploited for ‘garjan oil’, a balsam or resin, which is useful in making varnishes and lithographic inks; the timber of this tree is used for boat building and structural work. Drybalanops aromatica (East Indies) is the source of ‘Borneo camphor’ or ‘Sumatra camphor’. Hopea micrantha produces the valuable dammar called ‘mata kuching’. H. parviflora yields excellent timber which is particularly useful in pile and bridge construction.
A dark strong smelling thick balsam termed ‘chooa’ is obtained by distilling the resinous juice which exudes from the bark wound of Isauxis lanceaefolia (Bangladesh). Shorea aptera furnishes fats and oils. S. koodarsii provides a dammar resin, used as an incense. S. robusta is a timber tree and yields from the stem a resin known as ‘dhoona’ which is burnt as an incense; the seeds produce ‘sal butter’ which is used as an adulterant for ghee and instead of cocoa butter in the manufacture of chocolates.
The wood of Vateria indica is used as plank timber; oleoresin obtained from the trunk is ‘piney varnish’ when soft and ‘Indian copal’ or ‘Copal varnish’ when hard, being used for varnishing pictures and anatomical preparations, for making candles and ornaments; the seeds produce vegetable butter, ‘Malabar tallow’ or ‘Vateria fat’ or ‘piney tallow’, which finds use as a luminant, in confectionary and as a substitute for ghee; the bark is in demand in the manufacture of arak and jaggery. The starchy seeds of Doona, Vatica and Vateria acuminata are edible.
Family # 40. Dilleniaceae (Dillenia):
The presence of leaves with parallel lateral nerves, persistent calyx, numerous stamens in bundles, gynoecium of separate carpels, parietal placentation, seeds with a crested or laciniate aril and minute straight embryo are characteristic features of the Dilleniaceae.
The family is made up of 18 genera and 530 species of tropical regions, reaching the highest development in America and Australasia.
The fruits of Actnidia chinensis (eastern Asia) are edible. The leaves of Curatella americana (Central America) are sometimes used as sand paper. The fleshy sepals enclosing the fruits of Dillenia indica and D. pentagyna are used as vegetables. The species of Dillenia, Hibbertia and Tetracera are important as ornamentals.
Family # 41. Passifloraceae (Passion-Flower):
General Features of the Family:
Habit — Herbs or shrubs, climbing by tendrils.
Leaves — Alternate, simple, lobed. stipulate, often with glands on petiole.
Flowers — Bisexual or unisexual, regular; receptacle large, like a basin or cup and bears variously modified corona.
Calyx — Sepals 5, imbricate.
Corolla — Petals 5, sometimes absent, free, imbricate.
Androecium — Stamens 5, elevated by a gynandrophore; anthers 2-celled.
Gynoecium — Carpels 3-5; style free or united; ovary superior, unilocular; ovules several to many, anatropous; placentation parietal; stigma capitate.
Fruit — Berry or capsule.
Seeds — Many, often with a mucilaginously pulpy aril; embryo with a fleshy endosperm.
Number in and Distribution of the Family:
The Passifloraceae covers 20 genera and about 600 species. Though the members of the family spread over the warmer parts of the world, the chief centre of distribution lies in tropical America.
Commonly occurring Plants of the Family:
Adenia hondala (Gaertn.) de Wild, is found in Western Ghats and other moist hilly tracts in Peninsular India.
Passion-flower (Passiflora foetida L., P. lunata Juss. ex DC., P. suberosa L.) is a showy garden climber.
Economic Aspects of the Family:
Economically, the Passifloraceae is important for ornamentals and for edible fruits. The latter is produced by Passiflora edulis, P. laurifolia, P. ligularis, P. mollissima and P. quadrangularis.
Family # 42. Cochlospermaceae (Cochlospermum):
The family is akin to the Bixaceae, but differs from it in having palmately lobed leaves, three- to five-valved fruits and an oily endosperm.
The family represents two genera and about 38 species of tropical regions.
Cochlospermum religiosum bears large yellow flowers.
Cochlospermum gillivraei yields a useful ‘kapok’. C. religiosum is the source of ‘Kuteera gum’. The bark of C. vitifolium is used to make cordage.
Family # 43. Flacourtiaceae (Flacourtia):
The family can be diagnosed by the pellucid dotted leaves, polygamous flowers, undifferentiated perianth, enlarged receptacle, variously modified disc and numerous stamens.
The position of the Flacourtiaceae is uncertain. Hallier placed it in the Passionales, Hutchinson in the Bixales and others in the Parietales or Guttiferales.
The family takes into account 89 genera and about 1,250 species of the tropical and subtropical regions.
Flacourtia indica (Burm. f.) Merr. and F. jangomas (Lour.) Raeusch. are found throughout the greater part of tropical India.
The fruits of Aberia caffra (South Africa) and Flacourtia indica as well as F. ramontchi (Malagasy) are edible. Berberidopsis corallina, Carrierea calycina, Idesia polycarpa and Oncoba spinosa are noteworthy ornamentals. The wood of Casearia elliptica is used for carving and making combs. Gossypiospermum praecox (Venezuela) yields valuable timber. Hydnocarpus wightiana and Taraktogenos kurzii are the source of ‘chalmoogra oil’, used in the treatment of leprosy and other cutanous diseases. The seeds of Pangium editle (Malaya) are eaten after prolonged boiling in water to eliminate hydrocyanic acid.
Family # 44. Bombacaceae (Bombax):
General Features of the Family:
Habit — Tall trees, with thick trunks and spreading branches.
Leaves — Alternate, simple or palmately compound, stipulate.
Flowers — Showy, bisexual, regular, hypogynous.
Calyx — Sepals 5, united, valvate.
Corolla — Petals 5, free, imbricate.
Androecium — Stamens 5 to many, distinct or monadelphous; staminodes often present; anthers 1-, 2- or more-celled; pollen grains smooth.
Gynoecium — Carpels 2-5; ovary superior, 2- to 5-locular; placentation axile.
Fruit — Capsule with a woolly or pithy pericarp.
Number in and Distribution of the Family:
The Bombacaceae contains 20 genera and about 140 species, being prevalent in the tropics.
Commonly occurring Plants of the Family:
Baobab Tree (Adansonia digitata L.) is a “fantastic looking tree with a short trunk of considerable size close to the ground and tapering gradually upwards”.
Red Silk Cotton Tree (Bombax ceiba L.) is a tree with “a very striking feature in any landscape where it occurs, in the months of December, when it loses its foliage, and January, when it bursts into a blaze of scarlet flowers upon the naked branches”.
While Cotton Tree [Ceiba pentandra (L.) Gaertn.] is a tall tree with horizontally spreading branches.
Cullenia exarillata Robyns is a tall tree, found in Western Ghats.
Economic Aspects of the Family:
The acid pulp of the fruits of Adansonia digitata makes a good beverage. The seed hairs of Bombax ceiba yield floss for stuffing pillows, while those of Ceiba pentandra give us the so-called ‘kapok’. C. acuminata, C. aesculifolia and Chorisia insignis produce floss which can be used as an alternative for kapok.
Strong fibres are also obtained from the pods of C. speciosa (Brazil). The fruits of Durio zibethinus (Malaya) are edible, but taste like “French custard passed through a sewer pipe”. Ochroma pyramidala (South America) is the source of the world’s lightest commercial wood which has a specific gravity of 0.12.
Family # 45. Callitrichaceae (Water-Starwort):
In this family, the plants are aquatic herbs with opposite leaves. Here the flowers are unisexual and naked, the male consisting of a single stamen and the female of two carpels.
The genus Callitriche is of doubtful affinity and the position of the family is rendered obscure by the extremity in the reduction of vegetative and floral structure as well as vasculature. Hallier treated it as a primitive component of the Guttales, being derived from the Linaceae.
According to Eichler, Baillon, Wettstein, Pax and Rendle, the Callitrichaceae is an advanced member of the Euphorbiales. Clarke suggested that the family should be placed in the Caryophyllaceae. Robert Brown, de Candolle, Hegelmaier, Bentham-Hooker and others considered the family as related to the Haloragaceae.
Hutchinson placed the family in his Lythrales together with the Lythraceae, Onagraceae, Trapaceae and Holarrhagaceae. Others went to the extent of suggesting a relationship with the Sympetalae and this was based on the presence of unitegmic ovules.
The family has one genus (Callitriche) and about 17 species which are distributed from the arctic to subantarctic regions minus South Africa.
Callitriche stagnalis Scop, is a small flaccid herb, rooting at the nodes and with carpels narrowly winged at the margins.
In southern Germany, “it is possible to predict the abundance of certain pollutants by the species composition and state of Callitriche plants”.
Family # 46. Burseraceae (Incense-Tree):
The family is characterised by the presence of resin ducts, compound leaves, unisexual flowers, distinct stamens, a short single style and two ovules per loculus.
The Burseraceae is divided into three tribes:
Tribe (i) Bursereae:
Drupe with an endocarp of fused parts; exocarp always dehiscing by valves. Examples- Bursera, Commiphora, etc.
Tribe (ii) Canarieae:
Drupe with an endocarp of fused parts; exocarp not dehiscing by valves. Example- Canarium.
Tribe (iii) Protieae:
Drupe with 2-5, free or adhering parts but not fused in stony endocarp; exocarp occasionally dehiscing by valves. Examples- Protium, etc.
There are about 17 genera and 500 species in the Burseraceae. The members of this family reach their peak of development in north-eastern Africa and tropical America.
Boswellia serrata Roxb. ex Colebr., Bursera penicillata (Sesse & Moc. ex DC.) Engl., Garuga pinnata Roxb. and Protium serratum (Wall, ex Colebr.) Engl, are trees.
Several plants of the family are of value as a source of balsams, gums, resins, nuts and timbers. Boswellia carteri produces ‘gum olibanum’ and B.frereana ‘African elemi’. Indian frankincense is the product of B. serrata, ‘Mexican linaloe’ of Bursera glabrifolia and B. penicillata and ‘chibou’ of B. gummifera. Canarium commune provides ‘Java almond’ and C. ovatum ‘Pili nut’.
The wood of C. littorale, C. schweinfurthii, Dacrycodes costata, Santiria laevigata and S. tomentosa is used for carpentary and building construction. C. luzonicum supplies ‘Manila elemi’ and C. strictum ‘black dammar’. Commiphora africamun yields ‘African bdellium’, C. erythraea ‘herbol myrrh’ and C. opobalsamum ‘Mecca balsam’. ‘Carana gum’ is derived from Protium carana and ‘Brazilian elemi’ from P. heterophyllum. Some species of Bursera and Garuga are cultivated as ornamentals.
Family # 47. Simaroubaceae (Quassia):
The family is distinguished by the presence of a bitter bark, pinnate leaves, unisexual flowers, filament bases with scales and a single ovule per loculus.
The position of the genus Balanites is debatable. According to Record (1921), Balanites differs from zygophyllaceous taxa like Bulnesia, Guaiacum and Porlieria in xylotomy. However, it is similar to these taxa in having thick-walled fibres with bordered pits, abundance of fusiform parenchyma cells, small vessel pitting and vasicentric tracheids.
Heimsch (1942) considered that Balanites shows greater relationship to the Zygophyllaceae than the Simaroubaceae, although the genus can be set aside from the former family on the basis of the width and height of medullary rays. In floral anatomical features, the genus resembles the Zygophyllaceae.
In the basic chromosome number (x=9), B. aegyptiaca simulates Fagonia cretica of the Zygophyllaceae and Quassia amara of the Simaroubaceae (Darlingtoni and Wylie, 1961). Balanites resembles the Zygophyllaceae in essential embryological characters and differs from the Simaroubaceae in the smaller number of parietal layers, presence of endothecium and absence of nucellar cap Kapil and Ahluwalia, 1963; Nair and Jain, 1965; Davis, 1966.
Erdtman (1971) stated that the pollen grains of the Balanitoideae are akin to those of Harrisonia of the Simaroubaceae. Furthermore, B. roxhurghii exhibits the probable existence of saponins and steroids. In the absence of leucoanthocyanins, Balanites is more closer to the members of the Zygophyllaceae than those of the Simaroubaceae.
However, it differs from both taxa in the positive reaction for alkaloids. Hence, taking the totality of evidence, it has been tentatively suggested by Parvati and Narayana (1978) that Balanites be retained in the Zygophyllaceae but in subfamily Balanitoideae. But similarities with the Simaroubaceae do not rule out a probable common ancestral stock for the two taxa.
A family of about 20 genera and 120 species, the Simaroubaceae is found in the tropics and subtropics.
Ailanthus excelsa Roxb is a tall tree with much branched panicles. Balanites aegyptiaca (L.) Del. is a spiny tree, having flowers in small axillary cymes.
The family is important for ‘bitters’ prepared from the bark of many trees, e.g., Ailanthus excelsa, Balanites aegyptiaca and Simarouba amara. A. altissima. Kirkia acuminata, Picrasma excelsa and Simaba cedron yield valuable timber.
Family # 48. Oxalidaceae (Wood-Sorrel):
The family is recognised by the exstipulate leaves, actinomorphic flowers, imbricate calyx, contorted corolla, stamens connate at base, free styles, capsular fruit and seeds with an elastic testa.
The family comprises three genera and about 900 species, being prevalent in the tropics and subtropics and having richest representation in the Southern Hemisphere.
Biophytum sensitivum (L.) DC. is a weed of rice fields and road sides with a rosette of sensitive pinnate leaves and dimorphic flowers. Wood-sorrel (Oxalis corniculata L.) is a weed with ternate leaves, constructing a leaf mosaic.
Averrhoa bilimbi and A. carambola are grown for their acid fruits. The leaves of Oxalis acetosella are sometimes used in salads and stems of O. pescaprae used as a vegetable. O. crenata, O. deppei and O. tuberosa yield edible tubers.
Family # 49. Linaceae (Flax):
The family is known by the pentamerous actinomorphic flowers, contorted corolla of distinct and fugaceous petals, basally connate filaments, small staminodes and septicidally dehiscent capsule.
The phyletic position of the Linaceae is a matter of dispute. Bessey, Wettstein, Rendle, Lawrence and Core placed it in the Geraniales. Hallier shifted it to the Guttales. Hutchinson included it in the Malpighiales and Cronquist in the Linales.
The family represents 13 genera and about 300 species of the temperate and subtropical regions of both hemispheres.
The family is of importance for the Flax Plant (Linum usitatissinm), the bark of which yields a fine fibre for weaving into linen cloth. The seeds of this plant produce ‘linseed oil’ and the resulting oilcake is a cattle-feed. Ctenolophon parviflorum (Malaya) yields a hard durable timber. Hugonia obtusifolia and H. platysephala, both of Africa, provide edible fruits. A few species of Linum and Reinwardtia are cultivated ornamentally.
Family # 50. Erythroxylaceae (Coca):
The family is closely related to the Linaceae from which it is differentiated by the presence of monadelphous stamens, appendaged petals and drupaceous fruits.
The family was placed in the Linaceae by Bentham-Hooker and Hallier. Hutchinson transferred it to the Malpighiales. Most other workers treated it as a distinct family and as a member of the Geraniales.
The family covers four genera and about 260 species, being distributed in tropical America.
The leaves of Erythroxylum coca and E. truxillense are chewed by the people of Bolivia and Peru; this practice enables them to live without food or drink for several days. E. coca is also the source of ‘cocaine’; an extract of this alkaloid, together with cola, finds use in the manufacture of soft drinks.
Family # 51. Geraniaceae (Geranium):
The family is characterised by the pentamerous actinomorphic flowers, carpels splitting apart at maturity as mericarps and absence of endosperm.
The Geraniaceae embraces 11 genera and about 750 species. The members of this family are widely distributed in the subtropical and temperate regions.
Geranium ocellatum Jacq., found in the hills, is a straggling herb with rose coloured flowers.
In an economic sense, the family is of some importance. Erodium cicutarium is esteemed as a range forage plant. The roots of Geranium nepalense and G. wallichianum have astringent properties and are used as tanning material. The leaves of Pelargonium graveolens and P. odoratissimun yield, on distillation, ‘geranium oil’, an essential oil.
Family # 52. Zygophyllaceae (Caltrop):
The family is characterised by the pinnate or two foliolate leaves, persistent paired stipules, flowers with a prominent disc, free stamens bearing basal scales and carpels splitting apart at maturity as spiny or tuberculate nutlets.
The Zygophyllaceae takes into account 25 genera and 240 species. The members of this family are found generally in the drier areas of the world and particularly in the salt deserts.
Kallstroemia pubescens (G. Don) Dandy is a recently reported weed from West Bengal. Tribulus cistoides L. and T. terrestris L. are diffusedly branched prostrate herbs, the former without spiny fruits and the latter with spiny fruits.
The family is of economic value due to Guaiacum officinale which yields ‘lignum vitae’, one of the heaviest and hardest of commercial wood with a specific gravity of 0.95-1.25; it is also the source of ‘guaiacum’, a bitter resin, useful in medicine.
Other timber yielding plants include Bulnesia arborea, B. sarmientii and G. sanctum. Neoschroetera tridentata and Zygophyllum fabago are used medicinally. A few species are of ornamental value, i.e. those of Larrea, Tribulus, Zygophyllum, etc. Some species of Nitraria yield edible fruits.
Family # 53. Tropaeolaceae (Nasturtium):
The presence of long petioled alternate succulent leaves, zygomorphic flowers, distinct stamens and schizocarpic fruits are the characteristics of the Tropaeolaceae.
The family is composed of two genera and about 90 species extending from Mexico to Central Chile and Argentina.
Some species of the family are cultivated as ornamentals, e.g., Tropaeolum majus and T. peregrinum. The unripe seeds of T. majus are occasionally pickled. T. tuberosum (Andes) yields ‘cubios’, a type of edible tuber.
Family # 54. Malpighiaceae (Malpighia):
The family is diagnosed by the lianous habit, opposite leaves, appressed medifixed unicellular hairs, glandular calyx, clawed petals, peculiar anthers and lobed or winged fruits.
The Malpighiaceae is divided into two groups:
Group I. Planitorae:
Tours concave or flat. Mericarps not winged. Examples- Byrsonima, Malpighia, etc.
Group II. Pyramidotorae:
Torus pyramidal. Mericarps usually winged. Examples- Tetrapteris, etc.
The family is mostly treated as being akin to the Geraniaceae. Hairier placed it in the Polygalales. Hutchinson included it in the Malpighiaceae as derived from the tiliaceous stocks.
The family is represented by 60 genera and 800 species of the tropics, particularly in South America.
The family is of some economic significance. The bark of Banisteriopsis caapi, B. inebrious, B. quitensis and the species of Tetrapteris is used as the source of a narcotic beverage by the Indian tribes of the north-western part of the Amazon basin. Byrsonima spicata (West Indies) supplies ‘shoemaker’s bark’.
The leaves of Hiptage bengalensis are used to treat skin diseases. The fruits of Malpighia glabra are good for making preserves. Acridocarpus alternifolius, Banisteria laevifolia, Heteropterys beecheyana, Stigmaphyllon ciliatum, etc. make fine ornamentals.
Family # 55. Balsaminaceae (Jewelweed):
The family is recognised by the herbs with watery stems, irregular flowers, anthers connate around ovary and capsule with an explosive dehiscence.
The presence of nectariferous spur in the flower had led some botanists to link the Balsaminaceae with the Geraniaceae or Tropaeolaceae. While the spur is strictly an outgrowth of the calyx in the Balsaminaceae, receptacular tissues are involved in spur formation in the Geraniaceae and Tropaeolaceae. In the past, there was a general tendency to interpret the Balsaminaceae as a member of the Geraniales. The current view is to treat the family in the Sapindales.
The Balsaminaceae is composed of four genera and 500-600 species. The members of this family are widely distributed, especially in the tropics of Africa and Asia.
Hydrocera triflora (L.) Wt. & Arn. is an aquatic weed with floating fistular stem. Balsam (Impatiens balsamina L.) is a garden herb with showy variegated flowers.
The species of Impatiens are raised for their ornamental value, as the flowers are abundant and handsome.
Family # 56. Hippocastanaceae (Horse-Chestnut):
The family is characterised by the pinnately compound leaves, thyrsoid inflorescence, irregular flowers, simple stigma, coriaceous capsule and cotyledons adherent face-to-face.
A family of two genera and 25 species, the Hippocastanaceae abounds in the north temperate zone and South America.
Aesculus indica Colebr. ex Camb. is a very handsome tree from the Punjab and Uttar Pradesh.
Several species of the family are cultivated as ornamentals, e.g., Aesculus californica, A. glabra, A. hippocastanum and A. parviflora. The roots are crushed and used for washing woollen clothes. The seeds are utilised as fodder.
Family # 57. Celastraceae (Staff-Tree):
The family is known by the fasciculate or cymose flowers, ovary with a disc and berry or capsule in which the seeds are enveloped by a brightly-coloured aril.
The family embraces 55 genera and 850 species of wide distribution.
Cassine glauca (Rottb.) O. Kuntze is a graceful deciduous tree.
Economically, the family is of considerable importance. Cassine glauca produces wood for cabinet work; the root of this plant is used as an emetic and as a cure for snake bite. The buds and leaves of Catha edulis are used to prepare ‘Khat’, a beverage of the natives of Arabia.
The seeds of Kokoona zeylanica (Sri Lanka) act as a source of oil. The species of Celastrus, Euonymus, Pachystima, etc. are cultivated as ornamentals. Elaeodendron americanum, E.purpureus, Euonymus tingens, Hippocratea acapulcensis, Maytenus boania, M. ilicifolia and M. senegalensis, are of medicinal value.
Family # 58. Aceraceae (Maple):
The family is closely allied to the Sapindaceae from which it is distinguished by the opposite and palmate leaves, regular flowers and samaroid fruits.
The family comprises two genera and 102-152 species, being found in the temperate regions and tropical mountains.
Acer caesium Wall, ex Brandis is a tall deciduous tree from Himalayas.
A. macrophyllum, A. pseudoplatanus, A. rubrum and A. saccharinum produce valuable timber. A. nigrum and A. saccharophorum are tapped for the sweet sap which is used for making maple candy, maple sugar and maple syrup.
Family # 59. Rhamnaceae (Buckthorn):
General Features of the Family:
Habit – Shrubs or trees, often spiny.
Leaves – Alternate, simple unlobed, coriaceous, stipulate.
Inflorescence – Axillary cymes.
Flowers – Bisexual, regular, perigynous with a disc filling calyx tube.
Calyx – Sepals 4 or 5, united, valvate.
Corolla – Petals 4 or 5, clawed and horned.
Androecium – Stamens 4 or 5, free, antipetalous.
Gynoecium – Carpels 3; ovary superior or inferior, 3-locular with 1 erect basal ovule in each loculus.
Fruit – Berry, capsule, drape or samara.
Seeds – Albuminous or exalbuminous; embryo large and straight.
Position and Affinity of the Family:
In Bentham-Hooker’s arrangement, the Rhamnaceae appeared under the Celastrales after the Geraniales and before the Sapindales. Rendle placed the family under the Rhamnales lying between the Celastrales and Rosales. Lawrence included it in the Rhamnales between the Sapindales and Malvales. Hutchinson accommodated it in the Rhamnales between the Santalales and Myrsinales.
The Rhamnaceae bears an affinity with the Vitaceae from the standpoint of floral construction, but is distinguished from it by having simple leaves and receptacular cup.
Number in and Distribution of the Family:
The Rhamnaceae comprises 58 genera and about 900 species. The plants of this family are cosmopolitan in distribution.
Commonly occurring Plants of the Family:
Berchemia floribunda Wall, is a pretty shrub found in the sub-himalayan tracts.
Gouania tiliaefolia Heyne is a climber with inferior three-winged fruits.
Helinus lanceolatus Brand, is a cirrhose scandent shrub.
Ventilago denticulata Willd. is a strong climber.
Jujube Tree or Indian Plum (Ziziphus mauritiana Lamk.) is a small tree.
Ziziphus oenoplia (L.) Mill, and Z. xylopyrus Willd. are straggling shrubs.
Economic Aspects of the Family:
Many members of the Rhamnaceae are of value as drugs, for fruits, for timber and for other purposes. Some species of Berchemia, Ceanothus, Discaria, Hovenia, Noltea, Pomaderris, Reynosia, Ziziphus, etc. are grown ornamentally. C.reclinatus (tropical America) supplies ‘Mabee bark’.
The bark of Colubrina asiatica (Samoa) is used for cleaning mats. Frangula alnus, Maeosopis eminii and Z. chloroxylon produce valuable timber. The wood of Gouania domingensis is utilised for making chewsticks. The root extract of G. tiliaefolia (Philippines) is used as a substitute for soap.
While Hovenia dulcis yields and edible fruit axis, the fruits of Z. lotus, Z. mauratiana, Z. vulgaris and Z. xylopyrus are edible. ‘Black ironwood’, one of the heaviest of woods with a specific gravity of 1.3, is derived from Krugiodendron ferreum (West Indies). ‘Sap green’ pigment is the product of the berries of Rhamnus cathartica, R. frangula and R. purshiana (USA) are cultivated for their bark providing the purgatives, ‘frangula’ and ‘cascara sagrada’ respectively. ‘Lokao’ or ‘Chinese green’, a green powdery substance, is made from the bark of R. globosa and R.utilis.
The dried unripe fruits of R. infectoria furnish yellow and green dyes. The bark of Ventilago denticulata is used for making cordage; the root gives a red dye which is utilised for dyeing cotton fabrics and tassar silk. Extracts of V. oblongifolia (Malaya) is used as a poultice to cure cholera. The fruits of Z. joazeiro (Brazil) are used as fodder.
Family # 60. Vitaceae (Grape):
General Features of the Family:
Habit – Shrubs, climbing by leaf opposed tendrils.
Leaves – Alternate, simple or digitate, stipulate.
Inflorescence – Cymes, panicles, racemes or spikes, arising opposite to a leaf at node.
Flowers – Small, greenish, sometimes unisexual, hypogynous with a prominent disc.
Calyx – Sepals 4 or 5, toothed or entire, connate.
Corolla – Petals 4 or 5, caducous, sometimes connate.
Androecium – Stamens 4 or 5, antipetalous.
Gynoecium – Carpels 2, syncarpous; ovary partially sunk in disc, 2-to 6-locular, ovules 1-2 in each loculus, ascending with a ventral raphe-, placentation axile; stigma capitate or discoid.
Fruit – Berry.
Seeds – Embryo small; endosperm cartilaginous.
Position and Affinity of the Family:
Bentham-Hooker included the Vitaceae under the Celastrales after the Geraniales and before the Sapindales. In Rendle’s arrangement, this family appeared under the Rhamnales between the Celastrales and Rosales. Hutchinson placed the family in the Rhamnales lying between the Santalales and Myrsinales.
The Vitaceae descended from the Rutaceae by the disappearance of the antipetalous whorl of stamens. It stands very close to the Rhamnaceae with a similar floral structure. The Vitaceae, however, differs from the Rhamnaceae by the climbing habit, baccate fruit, albuminous seeds and small embryo.
Number in and Distribution of the Family:
The Vitaceae embraces 12 genera and approximately 700 species. Although plants belonging to this family are widely distributed in the tropical and subtropical areas of the world, some often extend into the temperate regions.
Commonly occurring Plants of the Family:
Cayratia carnosa (Lamk.) Gagnep. is a short herb without tendrils and with lower leaves about 60 cm across and the upper ones 15-30 cm across.
Cayratia pedata (Lamk.) Juss. ex Gagnep. and Cissus setosa Roxb. are found in the country sides.
Cissus quadrangularis L. is a climber with a jointed quadrangular herbaceous sympodial stem.
Cissus woodrowii (Stapf ex Cooke) Santapau is an erect shrub without tendrils.
Leea aequata L. is shrub which is 1.2-3.0 m in height.
L. herbacea Buch-Ham. is another shrub, attaining a height of 3.6-4.8 m.
Economic Aspects of the Family:
The family is of economic significance due to the various types of grape which arise from the species of Vitis, such as V. aestivalis (summer grape), V. labrusca (fox grape), V. riparia (forest grape), V. rotun- difolia (muscadine), V. vinifera (wine grape) and V. vulpina (winter grape).
“Apart from having edible fruits, the dried Grapes become Raisins and a seedless form provides Sultanas. Currants come from a Corinthian variety. In addition the seeds are the source of Grape seed oil used in the manufacture of soap, paints and (after refining) in certain foods. The waste products are used as cattle food, tannin and cream of Tartar”.
The stems of V. papillosa (Java) and V. sicyoides (Mexico) are utilised as cordage.
The Vitaceae has some medicinal importance. The herbaceous leaves of Cayratia pedata and Cissus setosa are roasted and oiled and then applied to boils to bring about suppuration.
The ornamental value of the family is enhanced by such plants as Parthenocissus tricuspidata and P. quinquefolia. Some species of Cissus and Rhoicissus are cultivated as desirable house plants.
Family # 61. Thymelaeaceae (Mezereum):
The family is characterised by the simple leaves, perigynous flowers, uniseriate gamosepalous perianth, petals reduced to hypanthial appendages, definite member of stamens and superior unilocular ovary.
The phyletic position of the Thymelaeaceae is debatable. Bessey treated the family in the Celastrales. Hallier interpreted it as the primitive group of his Daphnales—an order originating from the Linaceae. Engler and Rendle placed the Thymelaeaceae in the Myrtiflorae.
Lawrence and Core included it in the Myrtales. Hutchinson once suggested that the affinity of the family lay with the Caryophyllales through the Geraniales. This idea was later discarded with the statement appended as “I now consider the Thymelaeaceae to be the apetalous relatives of the Bixaceae, especially of the exotic family Flacourtiaceae”.
The family includes 45 genera and perhaps 500 species of cosmopolitan distribution, excepting the polar regions and concentrating in Australia, South Africa, Mediterranean area and the Steppes of central and western Asia.
The family is of economic importance. The resin impregnated wood of Aquilaria malaccensis is the source of ‘agaru’ of commerce. The fibrous inner bark of Daphne cannabina is utilised for preparing ‘Nepal paper’. The specie of Daphne, Dirca, Edgeworthia and Pimelea are cultivated ornamentally. The well-known ‘rice paper’ is made from E. tomentosa and Wikstroemia canescens. The lace-like inner bark of Lagetta lintearia is suitable for making dress.
Family # 62. Elaeagnaceae (Oleaster):
The family is recognised by the silvery or golden-brown stellate or lepidote scales that densely cover the leaves and achenes enveloped by a fleshy persistent perianth.
Many systematists have treated the Elaeagnaceae as being an ally of the Thymelaeaceae with the androperianth tube indicating a relationship between the two families and hence they are included under the Myrtales or Myrtiflorae. Hutchinson placed the Elaeagnaceae in the Rhamnales, suggesting it to be “a more advanced group then and related to the Rhamnaceae”.
The family contains three genera and about 50 species of largely steppe and rock plants with the centres of abundance in southern Asia, Europe and North America.
Economically, the family is of some importance. The species of Elaeagnus are cultivated as deciduous or evergreen shrubs. The fruit of E.angustifolia and Shepherdia argentea are edible. The fruits of Hippohae rhamnoides (France) are sometimes made into jelly or as a sauce eaten with fish and meat; the hard wood has been used for turnery.
Family # 63. Punicaceae (Pomegranate):
The family is closely allied to the Lythraceae from which it differs by the union of ovary with the receptacle.
A family of one genus (Punica) and two species, the Punicaceae extends from the Balkans to the Himalaya and Socotra.
Economically, the family is important for ‘pomegranate’, which is the fruit of Punica granatunr, a syrup made from the seeds is sold under the name of ‘grenadine’.
Family # 64. Combretaceae (Combretum):
Features of the Family:
Habit – Shrubs or trees, often climbing.
Leaves – Alternate or opposite, simple, exstipulate.
Inflorescence – Panicles, racemes or spikes.
Flowers – Bisexual or polygamo-dioecious, regular; floral axis forms a tube.
Calyx – Sepals 4 or 5, united, valvate.
Corolla – Petals 4 or 5, alternate with sepals.
Androecium – Stamens 4-5, in 1 whorl, or 6-10, in two whorls, inserted on tube or limbs of calyx.
Gynoecium – Carpel 1; ovary inferior, unilocular, ovules 2-6 in each loculus, pendulous and anatropous; style long, fili form, stigma pointed.
Fruit – Drupe, winged at angles.
Seeds – Exalbuminous; cotyledons irregularly folded or spirally rolled.
Number in and Distribution of the Family:
The Combretaceae comprises 20 genera and about 475 species. The plants belonging to this family are found in the tropical and subtropical regions of the world.
Commonly occurring Plants of the Family:
Anogeissus latifolia (DC.) Wall, ex Bedd. is a big tree, having a cluster of winged fruits.
Calycopteris floribunda (Roxb.) Lamk. is a diffuse or scandent shrub.
Combretum C. ovalifolium Roxb. and roxburghii Spreng. are large climbing shrubs.
Gyrocarpus jacquini Gaertn. is a large tree.
Lumnitzera racemosa Willd. is a small tree of the Sunderbans.
Drunken Sailor or Rangoon Creeper (Quisqualis indica L.) is a garden climber.
Systematic Botany:
Arjun Tree or White Murdah [Terminalia arjuna (Roxb. ex DC.) Wt. & Arn.], Bedda Nut or Beleric Myrobalan [T. bellerica (Gaertn.) Roxb. ex Fleming], Indian Silver Grey Wood or White Chuglam (T. bialata Steud.), Indian Almond or Malabar Almond (T. catappa L.), Black Myrobalan or Chebulic Myrobalan (T. chebula Retz.) and Laurel or Sain (T. tomentosa Wt. & Arn.) are trees with angled fruits.
Economic Aspects of the Family:
The Combretaceae has some economic value. The gum, exuding from the trunk of Anogeissus latifolia, is used for calico printing, paper sizing and confectionery. The fruits of Calycopteris floribunda are used in the treatment of jaundice.
The species of Combretum and Quisqualis are of ornamental significance. The young fruits of Terminalia bellirica and T. chebula are rich in tannin. The fruits of T. catappa are edible. T. ivorensis and T. superba, both of West Africa, are important sources of timber.
Family # 65. Rhizophoraceae (Mangrove):
General Features of the Family:
Habit – Shrubs or trees.
Leaves – Opposite, simple, stipulate, coriaceous.
Flowers – Bisexual, legular, epigynous.
Calyx – Sepals 4-8, valvate.
Corolla – Petals 4-8, fringed, convolute or inflexed in bud.
Androecium – Stamens 8 to many, located in outer edge of a lobed disc; anthers 4-celled with an introrse longitudinal dehiscence.
Gynoecium – Carpels 2-5, united; ovary superior, inferior or half-inferior, ovules 2 in each loculus, pendulous and anatropous; style 1, with a small unlobed stigma.
Fruit – Berry or capsule.
Floral Range in the Family:
The flowers are polygamo-dioecious or dioecious in Blepharistemma and Sterigmapetalum. In the latter, the petals are much divided. In Kandelia, the petals are divided into thread-like segments. Only in Anopyxis, Cassipourea and Gynotroches, the ovary is superior. In the remainder of the genera, the ovary is semi-inferior or inferior.
Number in and Distribution of the Family:
The Rhizophoraceae is composed of 16 genera and about 120 species. Many plants of this family form the characteristic vegetation of muddy tidal flats and shore lines throughout the palaeotropical regions of the world.
Commonly occurring Plants of the Family:
Blepharistemma membranifolia (Miq.) Ding Hou is a handsome straight stemmed tree.
Bruguiera gymnorrhiza (L.) Lamk is a large tree.
Carallia brachiata (Lour.) Merr. is an evergreen tree, having shiny leaves.
Ceriops tagal (Perr.) C.B. Robins is a large shrub of the Sunderbans.
Kandelia candel (L.) Druce is a small tree.
Rliizophora apiculata Bl. and R. mucronata Lamk. are small trees of the Sunderbans.
Economic Aspects of the Family:
Economically, the Rhizophoraceae is of some importance. The wood of Carallia integerrima is used for house building, furniture, cabinet making, ornamental panelling, picture frames, rice pounders, etc.; the leaf infusion is a substitute for tea in Malacca.
The bark-decoction of Ceriops tagal stops haemorrhage; tannin is extracted from the roots and fruits and a dye from the bark. Poga oleosa yields ‘poga nuts’. The wood of Rliizophora mucronata is used as fuel and for making charcoal; the bark is used for tanning and dyeing; the fruit is edible and a light wine is prepared from the juice by fermentation.
Family # 66. Lecythidaceae (Brazilnut):
General Features of the Family:
Habit – Shrubs or trees.
Leaves – Alternate, simple, not gland-dotted.
Inflorescence – Racemose or solitary.
Flowers – Large, bisexual, regular or irregular.
Calyx – Sepals 4-6, valvate or slightly imbricate.
Corolla – Petals 4-6, free or united into a tube.
Androecium – Stamens many, in several series, sometimes outer ones become staminodes and resemble a corona; anthers basifixed.
Gynoecium – Carpels 2-6 or more, united; ovary inferior.
Fruit – Berry or woody capsule.
Number in and Distribution of the Family:
The Lecythidaceae, with about 20 genera and 450 species, is centred in the wet areas of tropical South America with some representatives in Africa and Asia.
Commonly occurring Plants of the Family:
Barringtonia acutangula (L.) Gaertn. occurs along the banks of rivers and canals.
B. racemosa (L.) Spreng. is found in the Sunderbans.
Careya arborea Roxb. is a small tree.
Cannon ball Tree (Couroupita guianensis Aubl.) is a garden tree, being cauliflorous.
Economic Aspects of the Family:
Economically, the Lecythidaceae is of some importance. Barringtonia acutangula, Couroupita guianensis, Lecythis grandiflora and L. ollaria produce good timber. Edible nuts are furnished by Bertholletia excelsa, L. ollaria, L. usitata and L. zabucajo. The leaves of Careya arborea are used for making ‘bidis’ and for covering ‘Burmese cherroot’. ‘Bark cloth’ is made from the fibres, yielded by Couaratari tauari. Grias cauliflora is cultivated for the fruits called ‘anchovy pear’, useful in making pickles.
Family # 67. Haloragaceae (Water-Milfoil):
The family is known by the monoecious plants, unisexual flowers, stamens four or eight and inferior ovary with a solitary ovule in each loculus.
The family is divided into two subfamilies, one containing two tribes and the other without any:
Subfamily I. Haloragoideae:
Leaves exstipulate. Inflorescence small. Petals present or absent. Ovary 2- to 4-locular. Fruit dry.
Tribe (i) Halorageae:
Fruit indehiscent. Examples- Haloragis, Proserpinaca, etc.
Tribe (ii) Myriophylleae:
Fruit dehiscing into two or four nutlets. Example- Myriophyllum.
Subfamily II. Gunneroideae:
Leaves stipulate. Inflorescence large. Petals absent Ovary unilocular. Fruit succulent. Example- Gunnera.
The family has been interpreted as a reduced form of the Onagraceae. Hallier considered it as derived from the Nymphaeaceae and hence placed it in the Ranales. Hutchinson included it in the Lythrales, suggesting it as advanced over the Onagraceae.
There are seven genera and about 180 species in the Holoragaceae. The members of this family are widely distributed, but abundant in Australia.
Myriophyllum indicum Willd. and M. tuberculatum Roxb. are seer in the border of the salt lakes and other moist places near Calcutta.
Family # 68. Trapaceae (Water-Chestnut):
The family is often included in the Onagraceae from which it differ by the branched assimilatory roots, uniseriate multicellular hairs or petioles, pedicels and lower surface of leaves, floating leaves with inflated petioles, single whorl of stamens and one seeded drupe with two to four upwardly directed spines.
As early as 1898, Raimann created a family Hydrocaryaceae for accommodating the genus Trapa. This view received support from Wettstein (1935). Pulle (1938) stated that the family name should be changed to the Trapaceae in the absence of any genus like Hydrocarya. However, Bentham-Hooker (1883), Rendle (1925) and Hutchinson (1959) included the taxon in the Onagraceae.
Eames (1953) expressed the opinion that on anatomical evidence Trapa is not allied to the Onagraceae and does not belong to it; the vascular bundles here are without a cambium and sphaeraphides are of common occurrence. Gibbs (1958) cited the absence of raphides. in Trapa and their presence in the Onagraceae.
The embryological features of Trapa, such as semi-inferior and bilocular ovary, eight-nucleate embryosac, lack of endosperm, Solanad type of embryo, extremely well developed and haustorial suspensor and extremely unequal cotyledons, justify its removal from the Onagraceae and its assignment to the Trapaceae.
A family of one genus (Trapa) and about 30 species, the Trapaceae belongs to the Old World.
Water chestnut [Trapa natans L.var. bispinosa (Roxb.) Makino] is an aquatic herb with the floating leaves rhomboidal and submerged leaves pinnatipartite as well as root-like.
The fruits of Trapa are eaten either raw or cooked, the starchy cotyledon forming the edible part.
Family # 69. Araliaceae (Ginseng):
The family is characterised by the leaves with a stellate indumentum, umbellate inflorescence, pentamerous flowers, inferior uniovulate ovary and fruit a berry or drupe.
The family is divided into three tribes:
Tribe (i) Aralieae:
Petals imbricate, sessile with a broad base. Examples- Aralia, Panax, etc.
Tribe (ii) Mackinlayeae:
Petals valvate, shortly clawed. Example- Mackinlaya.
Tribe (iii) Schefflereae:
Petals valvate, not clawed. Examples- Hedera, Schefflera, etc.
The family contains about 65 genera and 700 species, having centres of distribution in tropical America and Indo-Malaysia.
Helwingia himalaica Hook. f. & Thorns, ex Clarke, common in Darjeeling, is an undershrub with unisexual umbels about the middle of the upper surface of the leaves as well as near the apex of the phyllodes. Heteropanax fragrans (D. Don) Seem is a small unarmed tree. Panax fruticosum L. is a garden shrub with decompound or dissected sheathing leaves. P. pseudo-ginseng Wall is a herb met with in Khasi Hills, Meghalaya. Schefflera venulosa (Wt. & Arn.) Harms, is a climbing shrub.
The family is of some economic importance. The species of Acanthopanax, Aralia, Dizygotheca, Fatsia, Polyscias and Schefflera as well as Hedera helix are grown as ornamentals. The wood of Acanthopanax ricinifolium (Japan) is used for making hats.
Medicinal extracts are made from Aralia cordata and A. racemosa. ‘Virginian sarsaparilla’ and ‘Ginseng’ are obtained from A. nudicaulis and Panax schinseng (Korea) respectively. The roots of P. quinquefolium (USA) serve as a stomachic and stimulant. The pith of Tetrapanax papyriferus (China) is used for making ‘rice paper’. Tieghemopanax murrayi produces valuable timber.
Family # 70. Cornaceae (Dogwood):
The family is recognised by the woody or subligneous plants, umbellate inflorescence, inferior ovary and fleshy indehiscent drupe or berry.
The family includes 13 genera and over 100 species. While most of the species are found in the temperate regions of Asia and North America, some occur in the tropics and subtropics of South America and New Zealand.
Benthamidia capitata (Wall.) Hara, found in the hills near Dehradun and Darjeeling, is a tree with decussate simple leaves and heads (umbels) of scentless yellow flowers, each head having an involucre of four large bracts. Mastixia rostrata Bl. occurs in Assam hills.
The family is of importance for ornamentals, e.g. Aucuba, Cornus, Davidia and Griselinia. C. florida, Cynoxylon nuttallii, Nyssa aquatica, N. sylvatica and Swida alternifolia yield timber. The fruits of Cornus mas are used for making preserves and for the alcoholic beverage ‘vin de cornouille’.
Family # 71. Clethraceae (Pepperbush):
The family is characterised by the shrubby habit, polypetalous corolla, anthers inflexed in bud, pollen grains single (and not in tetrads) and generally trilocular ovary.
Asa Gray accepted the family as a tribe bf the Ericaceae. This view has been followed by Bentham- Hooker and other systematists. Klotzsch’s contention that the taxon deserves the rank of the family was accepted by Drude and others. Hallier considered it as the primitive family of his Ericales, being derived from the Ochnaceae.
There is one genus (Clethra) and about 120 species in the Clethraceae which belongs to tropical America.
Several species of Clethra are grown ornamentally for their aromatic summer bloom, e.g., C. acuminatum, C. alnifolia, C. arborea, C. monostachya and C. tomentosa.
Family # 72. Pyrolaceae (Pyrola):
The family is recognised by the herbaceous habit, polypetalous corolla and uniformly loculicidal capsule.
The family is separated into two subfamilies:
Subfamily I. Monotropoideae:
Parasitic or saprophytic herbs without green colour, leaves being reduced to scales. Anthers opening by longitudinal slits and pollen grains simple.
Examples: Allotropa, Monotropa, Pterospora, Sarcodes, etc.
Subfamily II. Pyroloideae:
Green leafy herbs with somewhat scapose habit. Anthers opening by terminal pores and pollen grains in tetrads. Examples: Chimaphila, Moneses, Pyrola, etc.
Several botanists have expressed the view that the Pyrolaceae is not sufficiently distinct from the Ericaceae as to deserve the status of a separate family. Rydberg (1914) and Small (1914) recognised the Pyrolaceae as a distinct taxon, but segregated the saprophytic chlorophyll deficient Monotropoideae as the Monotropaceae.
Copeland (1947) discarded the idea that the Pyrolaceae and Monotropaceae constitute two different families apart from the Ericaceae. This idea was previously shared by Henderson (1920) who considered the Pyrolaceae as a subfamily sprung from the Andromedeae.
Wodehouse (1935) suggested that the single pollen grains of the Monotropoideae are unlike any other ericaceous pollen. According to him, the Monotropoideae is distinct from the Ericaceae and unlike the Pyroloideae.
The Pyrolaceae is closely related to the Ericaceae from which it differs by the incomplete septation of the ovary and the undifferentiated embryo. It may be derived from an ericaceous stock with poly petalous corolla, but the shrubby habit was lost in the course of evolution and the herbaceous habit gradually became saprophytic.
A family of ten genera and about 70 species, the Pyrolaceae abounds in the north temperate and arctic regions.
Monotropa uniflora L. and Pyrola rotundifolia L. are found in temperate Himalaya.
Family # 73. Ericaceae (Heath):
General Features of the Family:
Habit – Shrubs or trees, rarely herbs.
Leaves – Alternate, opposite or whorled, simple, exstipulate.
Inflorescence – Racemose or solitary.
Flowers – Bisexual, regular or irregular, hypogynous or epigynous.
Calyx – Sepals 4-5, free or united, persistent.
Corolla – Petals 4-7, united.
Androecium – Stamens 8-10, free, arising from a nectariferous disc; anthers 2-celled.
Gynoecium – Carpels 4-5, joined; ovary inferior or superior; placetation axile; style long; stigma capitate or lobed.
Fruit – Berry or capsule.
Seeds – Embryo small; endosperm fleshy.
Divisions of the Family:
The Ericaceae is divided into four subfamilies:
Subfamily I. Arbutoideae:
Petals united, deciduous. Anthers often with bristle-like appendages. Ovary superior. Fruit a berry or loculicidal capsule. Seeds triangular ovate, not winged. Examples- Arbutus, Epigaea, etc.
Subfamily II. Ericoideae:
Corolla persistent. Anthers appendaged. Fruit a loculicidal capsule. Seeds round, not winged. Examples- Calluna, Erica, etc.
Subfamily III. Rhododendroideae:
Petals sometimes free, deciduous. Anthers without appendages. Fruit a septicidal capsule. Seeds with a strongly ribbed coat, often winged. Examples- Daboecia, Ledum, Rhododendron, etc.
Subfamily IV. Vaccinioideae:
Petals united, deciduous. Ovary inferior. Fruit a berry. Examples- Thibaudia, Vaccinium, etc.
Number in and Distribution of the Family:
The Ericaceae contains about 100 genera and 3,000 species. The members of this family form the characteristic vegetation of many regions of acid soils, especially in moors, swamps and mountain slopes throughout the temperate areas of the world. They are also found to a limited extent in the arctic region and tropical mountains.
Commonly occurring Plants of the Family:
Gaultheria fragrantissima Wall, and Lyonia ovalifolia (Wall.) Drude are found in Khasi Hills, Meghalaya.
Rhododendron hookeri Nutt., a shrub of Darjeeling, Sikkim and Himalaya, is noted for its cluster of blazing red flowers.
Economic Aspects of the Family:
The Ericaceae is important for ornamentals which is contributed by the species of Arctostaphylos, Calluna, Erica, Pieris, Rhododendron, etc. The leaves of Agapetes saligna are used as tea substitutes. The foliage and twigs of Andromeda polifolia (Russia) are used for tanning purposes. Fruits of Arbutus unedo are used for making preserves and alcoholic drinks.
A. menziesii produces valuable timber. E. arborea (Mediterranean) provides ‘briar root wood’ which is used to make tobacco pipes. The leaves of Gaultheria procumbens furnishes ‘oil of wintergreen’, an essential oil, used for medicinal preparations. G. shallon forms iemon leafs, Ledum latifolium ‘Labrador tea’ and Vaccinium arctostaphylos ‘Broussa tea’. Many species yield edible fruits, e.g., Huckleberry (Gaylussacia baccata), Cranberry (Oxycoccus palustris), Blueberry (V. angustifolium, V. corymbosum, V. membranaceum, V. myrtilloides, V. ovatum, V. vacillans) and Cowberry (V. vitis-idaea).
Family # 74. Epacridaceae (Epacris):
The family is closely allied to the Ericaceae from which it differs by the single whorl of epipetalous stamens, one-celled anthers and tricarpellate gynoecium.
The Epacridaceae is separated into two subfamilies:
Subfamily I. Epacridoideae:
Stems without annular scars. Leaves rarely sheathing. Bracteoles usually persistent. Examples- Epacris, Leucopogon, etc.
Subfamily II. Richeoideae:
Stems with annular scars. Leaves sheathing. Bracteoles often caducous. Example- Richea.
The family includes 30 genera and about 400 species. They are chiefly found in Australia and Tasmania, but are also distributed in New Zealand, Hawaii, South America and India.
The family is important for ornamentals like the species of Cyathodes, Dracophyllum, Epacris, Leucopogon and Richea. The leaves and roots of Styphelia malayana (Malaysia) are used medicinally; the inner bark of stems is used for making canoes waterproof.
Family # 75. Diapensiaceae (Diapensia):
The families characterised by the pentamerous perianth, absence of a disc, stamens borne on the corolla and pollen grains not in tetrads.
The family comprises seven genera and 20 species, inhabiting the cooler and temperate regions of the northern hemisphere.
The family is important for ornamentals, e.g., the species of Diapensia, Pyxidanthera, Schizocodon and Shortia. The foliage of Galax aphylla are collected and preserved for decorative purposes.
Family # 76. Ebenaceae (Ebony):
The family is characterised by the absence of milky sap and presence of unisexual flowers, stamens twice as many as corolla lobes, multilocular ovary, ovules bitegmic and typically in pairs, styles two to eight as well as seeds with a small hilum.
The Ebenaceae contains five genera and 400-500 species. The members of this family are distributed in tropical and subtropical regions with the greatest development in India and Malaya.
Diospyros peregrina (Gaertn.) Gurke and Maba buxifolia Pers. are trees.
The family is of economic importance as a source of timber, e.g., Diospyros ebenum, D.kurzii, D. melanoxylon, D. montana, D. quaesita, D. reticulata and Euclea pseudoebenus. D. kaki, D. lotus and D. virginiana produce edible fruits. The leaves of D. tomentosa are used for rolling ‘bidis’. The fruits of D. peregrina is utilised for smearing the bottoms of boats and for steeping fish-nets in order to make them waterproof.
Family # 77. Styracaceae (Storax):
The family is recognised by the stellate or lepidote indumentum, linear anthers, imperfectly septate ovary and drupe.
A family of 12 genera and 180 species, the Styracaceae abounds in the warmer regions of eastern Asia, Mediterranean area, south-eastern United States as well as Central and South America.
Bruinsmia polysperma (Clarke) van Steenis occurs in Khasi Hills, Meghalaya.
The family is economically important for resins like ‘Siam benzoin’ obtained from Styrax benzoides and S. tonkinensis, ‘Sumatra benzoin, from S. benzoin and ‘storax’ from S. officinalis. S. japonica yields finegrained wood used in making umbrella handles; the seeds are the source of an oil.
Family # 78. Symplocaceae (Symplocos):
The family is known by the inferior and completely septate ovary as well as berry-like fruit with a persistent calyx.
The Symplocaceae, with one genus (Symplocos) and about 300 species, is found in tropical and subtropical Asia and America.
Symplocos paniculata Miq. is found in Assam hills.
The hard seeds of Symplocos laurina are strung as beads and put around the necks of children.
The bark of S. racemosa is used for dyeing; sometimes, it is powdered for ‘abir’, a colouring matter.
Family # 79. Oleaceae (Olive):
Habit – Shrubs or trees, climbing or erect.
Leaves – Opposite, simple or imparipinnate.
Inflorescence – Axillary or terminal, compound racemes.
Flowers – Polygamous or dioecious, regular, dimerous.
Calyx – Sepals 4, small, united.
Corolla – Petals 4-6, free or connate.
Androecium – Stamens 2, epipetalous; anthers with cells back to back.
Gynoecium – Carpels 2, united; ovary superior, 2-locular, ovules 2 in each loculus, anatropous, ascending or pendulous; style simple; stigma bilobed.
Fruit – Berry, capsule or drupe.
Seeds – Albuminous; embryo straight.
Floral Range in the Family:
The flowers are arranged in a cyme, as in Jasminum. In Syringa, the inflorescence is a compound raceme.
In general, the flowers are bisexual. Unisexual flowers, however, are found in Fraxinus as well as in some species of Olea.
The calyx is absent in Fraxinus excelsior. In some species of Jasminum, more than 5 sepals are seen.
The corolla is usually tubular or rotate in Jasminum, Ligustrum and Olea. The petals may be free or united. They are 6 in number in J. nudiflorum. The aestivation is imbricate in Jasminum and valvate in Syringa.
The stamens are usually 2 and transverse, but may be median. The number of stamens is 4 in Hesperelaea and Tessarandra.
The ovary is generally bilocular, but sometimes tri- or tetralocular.
Divisions of the Family:
The Oleaceae is divided into two subfamilies:
Subfamily I. Jasminoideae:
Fruit vertically constricted and divided into two parts. Seeds erect. Example- Jasminum.
Subfamily II. Oleoideae:
Fruit not vertically constricted. Seeds pendulous. Examples- Fraxinus, Syringa, etc.
Number in and Distribution of the Family:
The Oleaceae consists of 29 genera and about 600 species. The members of this family are found in the tropical, subtropical and temperate zones of the world, although they are concentrated in Australasia and South-east Asia.
Commonly occurring Plants of the Family:
Jasminum ongustifolium Vahl, J. multiflorum (Burm. f.) Andr. and J. sambac (L.) Ait. are garden plants.
Privet (Ligustrum robustum Bl.), Linociera ramiflora (Roxb.) Wall., Coral Jasmine or Sorrowful Tree (Nyctanthes arbor-tristis L.) and Olea dioica Roxb. are trees.
Economic Aspects of the Family:
The Oleaceae is of importance on account of fruits, timber, dyes and ornamentals. The plants which are cultivated ornamentally include Chionanthus, Forsythia, Jasminum, Ligustrum, Osmonthus, Phillyrea, Syringa, etc. Fraxinus americana, F. excelsior, F. nigra, F. oregona, F. ornus, F. quadrangulata.
Notelaea ligustrina, Olea europaea and O. laurifolia yield useful timber. The corolla of Nyctanthus arbortristis is rich in colouring matter and is utilised as an auxiliary to other dyes; the leaves are often used to polish wood instead of sand paper.
Family # 80. Loganiaceae (Logania):
General Features of the Family:
Habit- Herbs, shrubs or trees.
Leaves – Opposite, alternate or whorled, simple, stipulate.
Inflorescence – Cymose.
Flower – Bisexual, regular.
Calyx – Sepals 4 or 5.
Corolla – Petals 4-5, united.
Androecium – Stamens as many as corolla lobes, epipetalous and alternate with them.
Gynoecium – Carpels 2, united; ovary superior, 2-locular; placentation axile; style two-cleft.
Fruit – Berry, capsule or drupe.
Seed – Winged; embryo straight; endosperm bony or fleshy.
Floral Range in the Family:
The stamens are reduced to 1 in Usteria. The ovary is half inferior in Mitreola; it may be unilocular in some species of Strychnos and incompletely bilocular in Fagraea.
Divisions of the Family:
The Loganiaceae is divided into two subfamilies:
Subfamily I. Buddlejoideae:
Trichomes multicellular. Internal phloem absent. Leaves usually lobed or toothed. Flowers 4-merous. Endosperm cellular. Examples- Buddleja, Nuxia, etc.
Subfamily II. Loganioideal:
Trichomes unicellular, rarely multicellular. Internal phloem present. Leaves entire. Flowers 4-merous or 5-merous. Endosperm nuclear. Examples- Logania, Strychnos, etc.
Number in and Distribution of the Family:
The Loganiaceae is a family of about 30 genera and 600 species, being represented in the tropical, subtropical and temperate regions.
Commonly occurring Plants of the Family:
Buddleja asiatica Lour, is a large shrub.
Gelsemium elegans (Gardn. & Champ.) Benth. is a large climber with golden yellow flowers.
Mitrasacme alsinoides R. Br., a small weak annual herb, is found in waste places.
Economic Aspects of the Family:
Various species of Buddleja, Gelsemium and Spigelia are found in cultivation. Fagraea crenulata, F. elliptica and F. fragrans yield good timber. The roots of Gelsemium sempervirens constitute ‘false jasmine root’. The seeds of Strychnos ignatii are employed as a remedy for cholera.
The seeds of S. nux- vomica yield the alkaloids ‘brucine’ and ‘strychnine’. The seeds of S. potatorum are rubbed into a paste which, when added to dirty water, causes the impurities to settle to the bottom. S.spinosa produces edible fruits. The bark of S. toxifera produces ‘curare’ to poison arrows.
Family # 81. Polemoniaceae (Phlox):
The family is distinguished by the absence of milky sap and presence of gamosepalous calyx, stamens inserted at different levels on the corolla tube, tricarpellate ovary and indefinite ovules.
The flowers may be borne singly or arranged in dichasia. They are zygomorphic in Bonplandia and Loeselia. The corolla may be campanulate (Cobaea), infundibuliform to rotate (Polemonium) and salverform (Phlox). The corolla tube is filiform in some species of Gilia.
The family contains 18 genera and about 300 species, being mainly distributed in the western United States.
Economically, the family is important for a number of ornamentals contributed by the species of Cobaea, Collomia, Gilia, Linanthus, Phlox and Polemonium.
Family # 82. Hydrophyllaceae (Waterleaf):
The family is recognised by the tendency towards helicold cymes, imbricate aestivation of corolla, stamens without scales between the filaments, style usually deeply two-cleft and numerous ovules borne on parietal placentae.
The Hydrophyllaceae represents about 18 genera and 250 species. The members of this family are widely distributed, but abundant in western North America.
Hydrolea zeylanica (L.) Vahl, an annual herb, bears lanceolate leaves and bright blue flowers.
Hydrophyllum canadensis serves as a remedy for skin diseases. The species of Nemophila, Phacelia and Wiganda are cultivated as ornamentals.
Family # 83. Nolanaceae (Nolana):
The Nolanaceae is an anomalous family. On the basis of regular flowers, twisted aestivation and pentacarpellate ovary. Bentham-Hooker placed the family in the Convolvulaceae. Bessey included it, along with the Solanaceae, in his Polemoniales. Wettstein and Rendle recognised the family and set it up in the Tubiflorae. The presence of mericarpous fruits is suggestive of the Boraginaceae. The family is closely allied to the Solanaceae from which it differs by the fruit structure.
This is a family of two genera and 83 species, native to Chile and Peru.
Nolana paradoxa is cultivated as an ornamental plant.
Family # 84. Gesneriaceae (Gesneria):
The family is recognised by the nonparasitic habit, irregular flowers, unilocular ovary and parietal placentation.
The family is divided into two subfamilies:
Subfamily I. Cyrtandroideae:
Ovary superior. Seeds with a copious endosperm. Cotyledons become unequal after germination. Examples- Cyrtandra, Didymocarpus, etc.
Subfamily II. Gesnerioideae:
Ovary somewhat inferior. Seeds with little or no endosperm.
Cotyledons remain equal after germination. Examples- Besleria, Gesneria, etc.
As the Gesneriaceae is closely related to the Orobanchaceae, Scrophulariaceae and Bignoniaceae, it is often difficult to separate the four families. The Orobanchaceae is a parasitic and degenerated group of the Gesneriaceae which in itself is nonparasitic. They only difference from the Scrophulariaceae is the presence of unilocular ovary. The Bignoniaceae stands out prominent by the silique-like woody fruit and large generally winged seeds.
The family has about 125 genera and 2,000 species in the tropical and subtropical regions of both hemispheres.
Aeschynanthus bracteata Benth., an epiphyte, grows at an elevation of 3,048 m in the Darjeeling area. Corallodiscus lanuginosus (Wall, ex DC.) Burtt is a scapigerous herb. Platystemma violoides Wall., a herb, bears the solitary leaf on the plant as a highly developed cotyledon.
A number of the Gesneriaceae are cultivated as ornamentals, e.g. Achimenes, Columnea, Episcia, Haberlea, Jancaea, Ramoiida, Saintpaulia, etc.
Family # 85. Orobanchaceae (Broom-Rape):
The family is known by the root parasitism and lack of green colour. Besides, the flowers are zygomorphic, calyx valvate, stamens didynamous and ovary one-celled with two to six parietal placentae.
Due to the presence of unilocular ovary, the Orobanchaceae has been interpreted as a parasitic offshoot of the Gesneriaceae. It is also regarded as a continuation of parasitism which developed in the Scrophulariaceae. Again, the similarities in the development of gametophytes, endosperm, embryo and seed suggest a link between the Orobanchaceae and Scrophulariaceae; the former can be derived from the latter through a form like Striga orobanchoides.
With about 14 genera and 180 species, the members of the Orobanchaceae are inhabitants of the north temperate zone.
Aeginetia pedunculata (Roxb.) Wall, is a parasite on grasses. Orobancke cernua Loeffl. var. nepalensis DC. and O. indica Buch.-Ham. ex Roxb. are parasitic on the roots of Brinjal, Mustard, Poppy, Tobacco and other winter field crops on which they cause havoc if well established.
Family # 86. Lentibulariaceae (Bladderwort):
General Features of the Family:
Habit – Insectivorous herbs, aquatic or marshy.
Leaves – When submerged finely dissested, bearing bladders or utricles, or a rosette of simple and entire leaves when not submerged.
Flowers – Bisexual, irregular, hypogynous.
Calyx – Sepals 5, united, often 2-lipped.
Corolla – Petals 5, united, 2-lipped, lower lip spurred or saccate.
Androecium – Stamens 2, epipetalous; anthers 1-celled.
Gynoecium – Carpels 2, medianly placed, syncarpous; ovary superior, unilocular; ovules anatropous, many in each loculus; placentation free central, stigma sessile, 2-lobed with posterior lobe much reduced.
Fruit – Capsule.
Seeds – Small. 1 or many, exalbuminous.
Number in and Distribution of the Family:
The Lentibulariaceae is made up of four genera and about 180 species. The members of this family are widely found in the temperate and tropical zones of the world.
Commonly occurring Plants of the Family:
Utricularia ciurea Lour. and U. inflexci Forsk. var. ste llaris (L.f.) P. Taylor are floating herbs.
Economic Aspects of the Family:
The members of the Lentibulariaceae are of no economic importance except for raising species of Pinguicula as ornamentals in gardens and species of Utricularia as curiosities in aquaria.
Family # 87. Pedaliaceae (Benne):
General Features of the Family:
Habit – Herbs or undershrubs, with mucilage containing glandular hairs.
Leaves – Opposite or spirally arranged, simple.
Flowers – Bisexual, irregular, hypogynous.
Calyx – Sepals 5, united.
Corolla – Petals 5, united.
Androecium – Stamens 4, didynamous; small staminodes present.
Gynoecium – Carpels 2, syncarpous; ovary superior, 2- to 4-locular, loculi somewhat completely divided by false septa, 1 to many ovules in each loculus; placentation axile.
Fruit – Capsule or nut, commonly spiny.
Position and Affinity of the Family:
Saponins are lacking in all except Sesamum indicum where their doubtful presence is shown. Pedalium murex and S. indicum are devoid of tannins which doubtfully exist in Martynia annua and S. laciniatum. S. indicum and S. laciniatum show the presence of steroids, whereas both steroids and triterpenes are absent in M. annua and P. murex. M. annua and S. laciniatum differ from P. murex and S. indicum in possessing leucoanthocyanins.
It is evident from the above facts that M. annua resembles the other taxa of the Pedaliaceae in a majority of chemical features. On the basis of distributional pattern of phenolic acids, Das et al. (1985) supported the separation of Martynia from the Pedaliaceae into an independent family Martyniaceae.
Number in and Distribution of the Family:
The Pedaliaceae is composed of 12 genera and about 50 species. The members of this family are largely seashore or desert plants occurring in Indo-Malaysia. Malagasy, South Africa and tropical Australia.
Commonly occurring Plant of the Family:
Gingelly or Sesame (Sesamum indicum L.) is an oil seed crop.
Economic Aspects of the Family:
Economically, the Pedaliaceae is important as the source of ‘sesame oil’ which is extracted from the seeds of Sesamum indicum. Oil is also extracted from S. angustifolium seeds.
The leaves of Ceratotheca sesamoides and Pedalium murex are used as vegetables.
Family # 88. Martyniaceae (Devil’s-Claw):
Glutinous-villous herbs, exstipulate leaves, zygomorphic flowers, unilocular ovary, parietal placentation and woody capsule with a pair of horn-like prongs are distinctive of the Martyniaceae.
Found in tropical and subtropical America, the Martyniaceae is a small family with five genera and ten species.
Martynia annua L. is an annual herb.
Family # 89. Globulariaceae (Globularia):
The diagnostic characters of the Globulariaceae include the presence of exstipulate leaves, zygomorphic flowers surrounded by an involucre of bracts, reniform anthers opening by a single slit and unilocular ovary with pendulous ovules.
The Globulariaceae was accommodated in the Selaginaceae by Bentham-Hooker and merged with the Scrophulariaceae by Hallier. Engler, Bessey Wettstein, Rendle and Hutchinson recognised the separate entity of the family. Some derived the family from the Scrophulariaceae and others from the Lamiales; the latter appears more plausible, since the tubular calyx, markedly two-lipped corolla and didynamous stamens are suggestive of the Labiatae.
Two genera and about 30 species make up the family Globulariacdae which abounds in South Europe and the Mediterranean.
The family is of no major economic importance. A few species of Globularia are occasionally cultivated as rock garden plants.
Family # 90. Bignoniaceae (Bignonia):
The family is characterised by the predominantly lianous habit, compound leaves, zygomorphic flowers, anthers connivent in pairs, numerous ovules, silique-like woody capsule, larged winged seeds and absence of endosperm in seeds.
The Bignoniaceae is separated into four tribes:
Tribe (i) Bignonieae:
Usually tendrillate. Ovary completely bilocular, compressed parallel to septum. Capsule septifragal with winged seeds. Examples- Glaziovia, Oroxylum, etc.
Tribe (ii) Crescentieae:
Usually erect, plants. Ovary unilocular or bilocular. Fruit a berry or indehiscent. Seeds not winged. Examples- Crescentia, Kigelia, Parmentiera, etc.
Tribe (ii) Eccremocarpeae:
Tendrillate. Ovary bilocular. Capsule splits from below up. Seeds winged. Example- Eccremocarpus.
Tribe (iv) Tecomeae:
Rarely tendrillate. Ovary bilocular, compressed at right angles to septum or cylindrical. Capsule loculicidal with winged seeds. Examples- Catalpa, Jacaranda, Tecoma, etc.
Having about 120 genera and 650 species, the Bignoniaceae is largely a tropical family and is highly developed in northern South America where climbers constitute an important part of the forest flora.
Indian Cork tree (Millingtonia hortensis L. f.). Oroxylum indicum (L.) Vent, and Stereospermum personatum (Hassk.) Chatt. are road side trees. Tecoma stans (L.) HBK. is a scandent garden shrub.
Some plants of the Bignoniaceae produce useful wood, e.g. Catalpa bignonioides, C. bungei, C. speciosa and Cybistax donnellsmithii. The leaves of Cybistax antisyphilitica are used as the source of a blue dye.
Many are ornamentals like the species of Bignonia, Crescentia, Doxantha, Jacaranda, Kigelia, Paulownia, Tabebuia, etc. The fruits of Crescentia cujete form ‘calabash’ after the removal of the pulp and are used for holding liquids. The seeds of Oroxylum indicum are used as linings for hats and as stuffing material between layers of wicker work to make umbrellas.
Family # 91. Plantaginaceae (Plantain):
General Features of the Family:
Habit – Herbs.
Leaves – Alternate or opposite, simple, seemingly parallel-veined, basal, sheathing at base.
Inflorescence – Capitate or spicate on wiry or stout scapes.
Flowers – Bisexual, regular, hypogynous, tetramerous.
Calyx – 4-lobed, herbaceous, persistent.
Corolla – 3- to 4-lobed, scarious or membranous, generally salverform.
Androecium – Stamens 4, rarely 2 or 1, inserted on corolla tube and alternate with lobes, much exserted; anthers 2-celled, opening lengthwise; pollen grains dry, abundant and powdery.
Gynoecium – Carpels 2; united; ovary superior, 1- to 4-locular; style 1, filiform.
Fruit – Circumscissile capsule or bony nut.
Seeds – Embryo straight; endosperm fleshy.
Position and Affinity of the Family:
The Plantaginaceae is an anomalous taxon and hence of doubtful relationship. Bessey included it in his Primulales as allied to and originating from the Plumbaginaceae. Hallier as well as Wettstein placed the family in the Tubiflorae as related to the Scrophulariaceae. Rendle, Lawrence and Core recognised the family and retained it in the Plantaginales.
Hutchinson also did likewise, but derived the order from primulaceous ancestors. The family, according to Porter, “probably represents an offshoot from the Polemoniales or perhaps from the Primulales”. The family is very likely a reduced one, arising from a gamopetalous group with entomophilous flowers.
Number In and Distribution of the Family:
The Plantaginaceae comprises three genera and about 223 species. The members of this family are world-wide in distribution, but found mainly in the temperate zone and mountains of the tropics.
Commonly occurring Plant of the Family:
Plantago asiatica L. occurs at wet places and by roadsides in the hilly regions.
Economic Aspects of the Family:
The family is of medicinal importance for Plantago indica, P. ovata and P. psyllium, producing seeds which contain mucilaginous substance and are used as a mild laxative. Several species of Plantago are considered as troublesome weeds.
Family # 92. Caprifoliaceae (Honeysuckle):
The family is characterised by the opposite exstipulate leaves, stamens as many as corolla lobes and trilocular inferior ovary.
The inflorescence is a regular cyme in Leycesteria formosa, 2-flowered cyme in the species of Lonicera and a spike or raceme in Diervilla and Symphoricarpos. The flowers are regular in Sambucus and Viburnum, but slightly zygomorphic in Linnaea and Symphoricarpos as well as markedly zygomorphic in Lonicera.
The stamens are didynamous in Dipelta and Linnaea. The carpels are 5 in Leycesteria and some species of Sambucus, 4 in Symphoricarpos, 3 in most of the remaining genera and 2 in Diervilla. The ovules are numerous in Leycesteria, but the ovules may be 1 in each loculus (Sambucus, Triosteum, Viburnum).
The Caprifoliaceae comprises about 18 genera and 450 species. The members of this family are highly developed in eastern North America and eastern Asia.
Lonicera ligustrina Wall., a shrub of Khasi Hillis, bears flowers in pairs with connate ovaries. Sambucus javanica Reinw. ex Bl. is a large shrub whose leaves are imparipinnate.
Economically, the Caprifoliaceae is important for ornamentals, e.g., Abelia, Diervilla, Kolkwitzia, Leycesteria, Linnaea, Lonicera, Sambucus, Symphoricarpos, Viburnum and Weigela. The stem of Abelia triflora is used for making walkingsticks. Wine is prepared from the ripe fruits of Sambucus nigra. Edible fruits are borne by some species of Viburnum.
Family # 93. Adoxaceae (Moschatel):
The family contains a solitary species, Adoxa moschatellina L., which is widespread throughout the north temperate zone. It is a perennial herb with a small head of greenish flowers in which the stamens are twice as many as corolla lobes.
The Adoxaceae is an anomalous taxon, being of doubtful affinity. Most systematists have recognised it as a separate family. But the monotypic genus Adoxa was retained in the Caprifoliaceae by Bentham-Hooker. The general habit of the plant, coupled with the absence of a calyx and the fission of the stamens, would warrant its removal from the Caprifoliaceae.
The half inferior ovary and perhaps superficial resemblance of the flower to such a form as Chrysosplenium are suggestive of the Saxifragaceae. The inconspicuous flowers, associated with the half inferior isomerous ovary and the solitary pendulous ovule, call for an alliance with the Araliaceae.
Family # 94. Valerianaceae (Valerian):
The family is recognised by the opposite exstipulate leaves, irregular spurred or saccate flowers, annulate calyx, stamens fewer than corolla lobes and trilocular inferior ovary with a single fertile loculus.
The Valerianaceae is composed of thirteen genera and about 400 species. The members of this family mostly occur in the north temperate region, but are also found in the Andes of South America.
Nardostachys jatamansi (D. Don) DC. occurs in alpine Himalaya, while Valeriana officinalis Linn, and Valerianella dentata Poll, in Kashmir.
A few plants of the Valerianaceae are cultivated as ornamentals, e.g., Centranthus ruber and Feedia eriocarpa. Nardostachys jatamansi, Valeriana excelsa and V. officinalis are used medicinally. Valerianella chenopodifolia, V. locusta and V. olitoria are raised for their edible leaves.
Family # 95. Dipsacaceae (Teasel):
The family is readily identified by the opposite exstipulate leaves, compact flower heads, calyx divided into pappus-like segments, stamens fewer than corolla lobes and unilocular inferior ovary.
The family is divided into two tribes:
Tribe (i) Dipsaceae:
Flowers borne in capitula, outer often enlarged. Calyx bristly or scaly.
Stamens 4, rarely 2, similar. Example- Dipsacus.
Tribe (ii) Morineae:
Flowers borne in verticillasters in upper leaf axils. Calyx foliaceous. Stamens 2 or 4, dissimilar. Example- Morina.
The Dipsacaceae includes 11 genera and 350 species. The members of this family are inhabitants of the eastern Mediterranean and Balkan areas, but they extend eastwards across the Russian Steppes into India.
Several species of Ceplialaria. Morina, Pterocephalus and Scabiosa are cultivated for ornament. The ripened fruiting inflorescences of Fuller’s Teasel (Dipsacus sativus) are utilised for raising the nap (upon cloth); the dried flower heads are often used for winter bouquets. Some species of Scabiosa were formerly employed in the treatment of itch (scabies).
Family # 96. Campanulaceae (Bell-Flower):
General Features of the Family:
Habit – Herbs, shrubs or trees, with a watery or milky sap.
Leaves – Alternate, or opposite, simple, exstipulate.
Inflorescence – Monochasial or dichasial cymes.
Flowers – Bisexual, regular or irregular, epigynous.
Calyx – Sepals 5, united, imbricate or valvate.
Corolla – Petals 5, united, valvate.
Androecium – Stamens 5, alternate with petals, free or variously united; anthers 2-celled.
Gynoecium – Carpels 2-5; ovary inferior, unilocular, ovules many, placentation axile.
Fruit – Berry or capsule.
Seeds – Embryo small; endosperm fleshy.
Divisions of the Family:
The Campanulaceae is divided into three subfamilies:
Subfamily I. Campanuloideae:
Flowers actinomorphic, rarely slightly zygomorphic. Anthers generally free. Example- Campanula, Micluiuxia, Phyteuma, etc.
Subfamily II. Cyphioideae:
Flowers zygomorphic. Stamens with filaments united, but anthers free. Example- Cyphia.
Subfamily III. Lobelioideae:
Flowers markedly zygomorphic, rarely almost actinomorphic. Anthers united. Examples- Lobelia and Siphocampylus.
Number In and Distribution of the Family:
A family of about 35 genera and 600 species, the Campanulaceae is mostly subtropical or temperate and also has representatives in mountains of the tropics.
Commonly occurring Plants of the Family:
Lobelia alsinoides Lamk., Pratia begonifolia Lindl. and Wahlenbergia marginata (Thunb.) A.DC. are herbs.
Sphenoclea zeylanica Gaertn., an aquatic fleshy herb, bears alternate leaves, bracteate spikes and white flowers.
Economic Aspects of the Family:
Adenophora, Campanula, Codonopsis, Edrianthus, Jasione, Lobelia, Michauxia, Ostrowskia, Platycodon, etc. are cultivated as ornamentals. The roots and leaves of Campanula rapunculus are edible. Lobelia inflata is a medicinal plant which contains ‘lobeline’, a volatile alkaloid.
Family # 97. Goodeniaceae (Goodenia):
The family is very close to the subfamily Lobelioideae of the Campanulaceae. However, it is distinguished by the absence of milky sap, presence of extra fascicular cambium in the stem and development of indusiate pollen collecting cup subtending the stigmas.
The Goodeniaceae includes 13 genera and 300 species. The members of this family are primarily distributed in Australia, but are also found in New Zealand, Polynesia and other tropical coasts.
The family is of economic importance only for Scaevola koenigii which yields ‘Taccada pith’. Many species of Dampiera, Goodenia, Leschenaultia and Scaevola are cultivated as ornamentals.
Family # 98. Stylidiaceae (Stylidium):
The family is recognised by the peculiar gynostemium, stamens 2-3, extrorse anthers and free central placentation.
The family covers six genera and about 150 species, being prevalent in tropical Asia, Australia, New Zealand and South America.
Stylidium kunthii Wall, is found in Khasi Hills and Sikkim.
A few species of Stylidium are cultivated for ornament.
Family # 99. Betulaceae (Birch Family):
General Features of the Family:
Habit – Shrubs or trees, with perulate buds.
Leaves – Alternate, simple, stipulate.
Inflorescence – Male flowers in pendulous catkins and females in cylindrical cone-like spikes.
Flowers – Unisexual.
Androecium – Stamens 1-4; anthers basifixed.
Gynoecum – Carpels 2, united; ovary inferior.
Fruit – 1-seeded nut, subtended by foliaceous bracts.
Divisions of the Family:
The betulaceae is divided into two subfamilies:
Subfamily I:
Betuloideae. Male flowers in 3-flowered dichasia in axil of a bract and have a perianth. Female flowers lack a perianth. Examples: Alnus and Betula.
Subfamily II:
Coryloideae. Male flowers solitary, without a perianth. Female flowers have a perianth. Examples: Carpinus, Corylus, etc.
Number and Distribution of the Family:
There are six genera and approximately 170 species in the Betulaceae, mostly distributed in the cooler portions of northern hemisphere but also in tropical Andes and Argentina.
Commonly Occurring Plants of the Family:
Himalayan Black Cedar (Alnus nitida Endl.), a deciduous tree, is found in western temperate Himalaya.
Paper Birch (Betula utilis D. Don) is a tree with the bark peeling off in horizontal flakes or plates.
Economic Aspects of the Family:
The Betulaceae contains many useful plants. Alnus glutinosa is used for preparing high grade charcoal. A. nitida, A. rubra, Betula lenta, B. lutea, B. pendula, B. pubescens, Carpinus betulus, C. caroliniana and Ostrya carpinifolia produce valuable timber. Birch beer is made from the sugary sap of Betula sp. and ‘oil of betula’ from twigs of the same. Some species are popular as ornamentals, such as B. alba and B. papyrifera.
The bark of B. papyracea is used for making canoes. The outer bark of B. utilis is employed as a material for writing upon. Edible Hazelnuts are derived from Corylus americana and C. cornuta as well as Filberts from C. avellana, C. colurna and C. maxima.
Habit – Shrubs or trees, deciduous or evergreen.
Leaves – Alternate, simple, stipulate.
Inflorescence – Male flowers usually in catkins and females in few flowered clusters.
Flowers – Unisexual.
Perianth – Present, 4- to 7-lobed in male flowers and 4- to 8-lobed in female flowers.
Androecium – Stamens 4-40; anthers basifixed.
Gynoecium – Carpels 3, united; ovary inferior.
Fruit – 1-seeded nut, invested by a cupule.
Family # 100. Polygalaceae (Milkwork Family):
General Features of the Family:
Habit – Herbs, shrubs or trees, sometimes twining.
Leaves – Alternate, simple, entire, exstipulate.
Inflorescence – Panicles, racemes or spikes.
Flowers – Bisexual, irregular, subtended by bracts and bracteoles.
Calyx – Sepals 5, inner 2 large, petaloid and wing-like.
Corolla – Petals usually 3, lower median forming a keel and often bearing a dorsal fimbriated appendage.
Androecium – Stamens 3-10, monadelphous beyond middle’, anthers 1-celled, opening by apical pores.
Gynoecium – Carpels 2-5, united; ovary superior, usually 2-locular, placentation axile.
Fruit – Capsule, drupe, nut or samara.
Seeds – Pilose with a conspicuous strophiole; embryo axial, straight, endosperm soft, fleshy.
Position and Affinity of the Family:
There is little agreement with respect to the phylogenetic position of the Polygalaceae. Warming included it in the series Sapindales and after the Aceraceae. Engler and Bessey placed it in the Geraniales. Wettstein put it in the Terebinthales.
In the arrangement of Bentham-Hooker, it appeared between the Parietales (Papaveraceae, Cruciferae etc.) and Caryophyllinae. It was treated within the Polygalales by Hallier as well as Hutchinson. Chodat suggested that the Polygalaceae is “a very natural family, not closely allied with any other”. Rendle regarded the family as of doubtful position.
Number and Distribution of the Family:
The family is made up of 17 genera and 1,000 species of cosmopolitan distribution, except for the arctic zone, Polynesia and New Zealand.
Commonly Occurring Plants of the Family:
Polygala arillata Buch.-Ham. ex D. Don, found in Shillong, is a graceful shrub.
Polygala chinensis L. is a well-known weed in pastures.
Xanthophyllum flavescens Roxb., a large tree of Darjeeling, bears pink and yellow panicles.
Economic Aspects of the Family:
Economically, the Polygalaceae is of slight importance. The species of Comesperma, Polygala and Securidaca are grown as ornamentals. A few species of Polygala yield dyes. P. butyracea (tropical Africa) produces a fibre. The dried roots of Polygala senega (USA) form the source of a glucosidal drug called ‘senega’.
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