Family- Ranunculaceae
There are about 35 genera and 1500 species in this family.
Distribution: They are chiefly found in the temperate and other colder part of the world. In our country, the plants are chiefly found in the hilly regions. The species of Clematis are found in the Western Himalayas upto 5,000 feet. Thalictrum javanicum found to be distributed from Simla to Sikkim hills. The species of Ranunculus are found in the Indian plains.
Habit: Generally the plants are annual or perennial herbs. They perennate either by means of rhizomes or by tuberous roots, e.g., Ranunculus, Paeonia, etc. Under shrubs, and shrubs are also found in this family. Usually the species of Clematis are climbing under shrubs. The species of Naravelia are also climbing shrubs.
Leaf: The leaves are alternate, exstipulate and more or less divided. In some cases the leaves may be opposite or even radical. In Clematis, the leaves are opposite and compound. They possess twinning petioles. In Anemone the leaves are radical. The leaf base usually broadens into a sheath which sometimes elongates into a pair of lateral stipules, e.g., in Thalictrum. Heterophylly is found in the aquatic species of Ranunculus. In such cases the submerged leaves are very much dissected whereas the floating ones are simply lobed. In Delphinium the leaves are palmately lobed and much dissected.
Inflorescence: In most of the cases the inflorescence is of cymose type, e.g., Ranunculus. The flower are often solitary and terminal, e.g., Anemone sp. In Aconitum and Delphinium, the inflorescence is of racemose type. In Clematis cadmia the inflorescence is solitary axillary.
Flower: The flower are ebracteate, hermaphrodite and mostly actinomorphic(regular), rarely they are zygomorphic(irregular) such as Delphinium and Aconitum, hypogynous. The flowers are usually developed on an elongated receptacle. The floral parts being arranged wholly or partly spirally.
Perianth: In most of the flowers of this family, the perianth is not distinguished into calyx and corolla. It is simple, petaloid and variously coloured. However, in Ranunculus there are two distinct whorls of calyx and corolla, each consisting of five sepals and five petals, respectively. The perianth is often associated with nector secreting structures of various forms. In Ranunculus, the petals posses pocket like nectaries at their bases. The number of perianth leaves varies from four to twenty.
Androecium: Usually the number of stamens is indefinite. The stamens are free(Polyandrous). They are hypogynous and arranged spirally. Mostly the anthers are extrorse, basifixed and dithecous. They dehisce laterally.
Gynoecium: It consist of indefinite carpels(polycarpellary). The carpels are free, apocarpous. In Delphinium the number of carpels is reduced to one. In Aconitum sp., there are three to five carpels. In Nigella, there are five to eight carpels, which are more or less united(syncarpous). In each ovary the number of ovules ranges from one to many. The ovules are anatropous. The placentation marginal(e.g., Dalphinium), or basal(e.g., Ranunculus).
Fruit: The fruit is usually either an etaerio of achenes, e.g., Ranunculus or an etaerio of follicles, e.g., Aconitum. In some of the cases the achenes possess long persistent feathery styles which help in the distribution of the fruits by means of wind, e.g., Clematis and Anemone.
Seed: The seeds are endospermic. Each seed contains oily endosperm with a very small embryo.
Pollination: The pollination takes place either by means of insects(entomophily) or by wind(anemophily). The flowers of Delphinium and Aconitum are pollinated by long tongued bees.