GERANIACEAE

Pelargonium x hortorum

Pelargonium x hortorum

FAMILY OF THE WEEK : GERANIACEAE
A family of 5 genera and 570 species and is cosmopolitan in distribution. In India 3 genera and 25 species occurring mostly in Himalayas: wild and cultivated variety.
Vegetative characters:
Mostly herbs.The plants perennate by fleshy rhizomes or bulbous tubers.The stem is succulent and contains watery juice. The plants are glabrous or more commonly glandular pubescent.
The leaves are opposite or alternate, simple or often lobed or divided as in geranium. The stipules are usually present.
Inflorescence and flowers:
The commonest form of inflorescence is cymose.
The flowers are bracteate and usually bracteolate,complete,hermaphrodite,actinomorphic or zygomorphic,pentamerous and hypogynous.
The calyx is of five sepals which are free or rarely united, persistent, imbricate or rarely valvate.The corolla is also composed of five free petals alternating with sepals. The receptacle is scarcely expanded into a disc which has five glands. Usually there are ten stamens in two alternate whorls of five each.The anthers are diathecous introrse and dehiscing longitudinally.In Geranium a nectary is present at the base of each stamen of the inner whorl.
The gynoecium is usually five carpellary and syncarpous with a superior pentalocular ovary. The style is long with five stigmas.
Fruits and seeds:
Fruit is a schizocarpic.Often beaked and five lobed.
Pollination is by a variety of bees which visit the flowers for nectar.The seeds are scattered in all directions as the capsule opens by violence.
Examples:
Geranium wallichianium
Geranium robertianum
Erodium sp.
Pelargonium