EUPHORBIACEAE

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            1. SYSTEMATIC POSITION:
            Bentham & Hooker
            Division: Phanerogames (Seed Plants)
                 Class: Dicotyledones
                        Sub-class: Monochlamydeae
                               Series: Unisexualies
                                      Family: Euphorbiaceae
           
           
            2. MORPHOLOGICAL CHARACTERS:
            Habit – Mostly annual or perennial herbs, aromatic.
            Leaves – Alternate or sometimes opposite, simple or rarely compound, stipulate, hairy and sometimes replaced by glands, hairs and thorns.
            Inflorescence – Variable, often racemose and subsequent ones cymose or all cymose. Characteristic inflorescence is cyanthium.
            Perianth – Tepals 3-5 or 0, green and rarely petaloid, disc entire or variable number of glands.
            Androecium – Stamens 1-many, filaments branched or connate in many bundles, anther dithecous.
            Gynoecium – Carpel 3, syncarpous, ovary 2-4 locular, superior, ovules 1 to 2 in each loculus, placentation axile, style 3, each bifid, stigma 6.
            Fruit – Usually schizocarpic, regma splitting into 3 cocci, rarely drupe, capsule or nut.
           
            3. FLORAL FORMULA:   Male flower:      ⊕♂P3-5 or (5+5), A1-α                             
                                                         Female Flower: ⊕♀P3-5 or (5+5), G(3) or more
           
            4. COMPARATIVE SYSTEMATIC POSITION AND AFFINITIES:
            Euphorbiaceae is closely allied to the members of the order Malvales. This family is also related to the members of the order Gereniales and Sapindales on account of the nature of ovules. It is related to the family Sterculaceae in particular due to the presence of monoadelphous stamen, rudiments of stamens and carpels, androphore and gynophores occasionally and the nature of embryo.
            It has been suggested that the Euphorbiaceae arose from the Malvales. The members of Euphorbiaceae seems to be highly specialized in the presence of reduced flowers in many, flower like inflorescence (Cyathium) in Euphorbia and some other genera and milky latex.
            5. ECONOMIC IMPORTANCE:
            1. The bio-diesel crop Jatropa curcus belongs to this family.
            2. The rubber of commerce is obtained from the species of Hevea like H. brasilensis.
            3. Ricinus communis is the source of castor oil.
            4. Cultivated ornamental plants are Codiaeum variegatum, Pionsettia pulcherrima, Acalypha hispida, A. wilkesiana, etc.
            5. Plants with medicinal values are Croton spp., Acalypha indica, etc.
            6. The tuberous root of Manihot utilisima is the source of starch.
           
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