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''Geranium'' is a genus of 422 species of flowering annual, biennial, and perennial plants that are commonly known as the cranesbills. They are found throughout the temperate regions of the world and the mountains of the tropics, but mostly in the eastern part of the Mediterranean region. The long, palmately cleft leaves are broadly circular in form. The flowers have five petals and are coloured white, pink, purple or blue, often with distinctive veining. Geraniums will grow in any soil as long as it is not waterlogged. Propagation is by semiripe cuttings in summer, by seed, or by division in autumn or spring. The genus name is derived from the Greek (''géranos'') or (''geranós'') ‘crane’. The English name ‘cranesbill’ derives from the appearance of the fruit capsule of some of the species. Species in the ''Geranium'' genus have a distinctive mechanism for seed dispersal. This consists of a beak-like column which springs open when ripe and casts the seeds some distance. The fruit capsule consists of five cells, each containing one seed, joined to a column produced from the centre of the old flower. The common name ‘cranesbill’ comes from the shape of the unsprung column, which in some species is long and looks like the bill of a crane. However, many species in this genus do not have a long beak-like column. Geraniums are eaten by the larvae of some Lepidoptera species including brown-tail and mouse moth. The species ''Geranium viscosissimum'' (sticky geranium) is considered to be protocarnivorous. ==Confusion with pelargoniums== Confusingly, "geranium" is also the common name of members of the genus ''Pelargonium'' (sometimes known as 'storksbill'), which are also in the Geraniaceae family. These are generally half-hardy plants which are either grown from seed every year, or offered as bedding in spring and discarded after flowering. Linnaeus originally included all the species in one genus, ''Geranium'', but they were later separated into two genera by Charles L’Héritier in 1789. Other former members of the genus are now classified in genus ''Erodium'', including the plants known as filarees in North America. The term "hardy geranium" is often applied to geraniums to distinguish them from the pelargoniums. However, not all geranium species are winter-hardy (see below). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Geranium」の詳細全文を読む スポンサード リンク
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