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Wednesday, 21 January 2009

FAMILY OF THE WEEK: SCROPHULARIACEAE


Rhamphicarpa

Verbascum chinens

Lindernia ciliata

FAMILY OF THE WEEK: SCROPHULARIACEAE
This family is cosmopolitan in distribution but most abundant intemperate regions. In India it is represented by 57 genera and 350 species occurring chiefly in Himalayas.
Vegetative characters:
Mostly annual or perennial herbs, sometimes shrubs (Veronica) or rarely trees(Wightia). Certain members are aquatic(Limnophila) or marsh (Departrium and Herpestis) Some are chlorophyll containing hemiparasites(Pedicularis and Striga) or parasites without chlorophyll as Lathraea.
Usually the lower leaves are opposite and upper alternate.They are simple exstipulate entire or pinnately lobed or incised.
Inflorescence and flowers:
Variable but commonly racemose or spicate. Sometimes cymose or axillary solitary.The bracts and bracteoles are usually present.
The flowers are perfect, hermaphrodite,zygomorphic or sometimes as in Verbascum nearly actinomorphic and hypogynous.The calyx is deeply five lobed or divided, persistent, imbricate or valvate. The corolla is gamopetalous and the limb is usually free and more or less bi-lipped.Commonly five stamens are fertile and the fifth is reduced to a staminode or is completely absent.The stamens are epipetalous. the anthers are dithecous but occasionally the two cells are unequal or only one cell is present. The gynoecium is bicarpellary and syncarpous with a superior bilocular ovary. The style is simple and the stigma is capitate, bilobed or bi-lamellate.
An annular or cup shaped nectariferous disc is present at the base of the ovary which is sometimes bilobed.
Fruits and seeds:
The fruit is a capsule or rarely a berry. the seeds are small with a fleshy endosperm and straight or slightly curved embryo.
Pollination and dispersal:
The flowers are adapted for insect pollination. The seeds are dispersed by water, birds or animals.
Examples:
Antirrhinum majus (Snapdragon)
Digitalis purpurea (Common foxglove)
Linaria vulgaris
Verbascum chinens
Rhamphicarpa
Lobelia nicotianifolia(Ran Tambaku)
Lindernia ciliata

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