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BOTANY Higher Secondary Second Year - Textbooks Online

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DICOT FAMILIES<br />

1.3.1 MALVACEAE - the cotton family<br />

Systematic position<br />

Class: Dicotyledonae<br />

Sub-class: Polypetalae<br />

Series: Thalamiflorae<br />

Order: Malvales<br />

Family: Malvaceae<br />

General characters<br />

Distribution<br />

This family includes about 82 genera and more than 1,500 species.<br />

The plants are cosmopolitan in distribution, more abundant in tropical and<br />

subtropical regions. In India, Malvaceae is represented by 22 genera and<br />

125 species.<br />

Habit<br />

Plants may be annual herbs ( eg. Malva sylvestris) or perennial shrubs<br />

(eg. Hibiscus rosa-sinensis) or trees (eg. Thespesia populnea). The<br />

members of this family have mucilagenous substance. Stellate hairs occur<br />

on their young parts.<br />

Root<br />

Tap root system.<br />

Stem<br />

Aerial, erect (eg. Malva sylvestris), branched, woody (eg. Thespesia<br />

populnea), decumbent as in Malva rotundifolia (Thirikalamalli) and usually<br />

covered with stellate hairs.<br />

Leaf<br />

Petiolate, simple, entire (eg. Thespesia populnea) or palmately lobed<br />

(eg. Gossypium arboreum), alternate, stipulate, margins usually toothed<br />

(eg. Hibiscus rosa-sinensis) and showing reticulate venation.<br />

Inflorescence<br />

Solitary, terminal (eg. Malvastrum coromendelia) or solitary, axillary<br />

(eg.Thespesia populnea) or terminal or axillary cyme.eg.Pavonia odorata<br />

(Peramutti).<br />

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