LAMIACEAE

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1. SYSTEMATIC POSITION:
            Bentham & Hooker
            Division: Phanerogames (Seed Plants)
                  Class: Dicotyledones
                         Sub-class: Gamopetalae
                                 Series: Bicarpellatae
                                       Order: Lamiales
                                              Family: Lamiaceae
           
            2. MORPHOLOGICAL CHARACTERS:
            Habit – Herbs or shrubs, often aromatic with quadrangular stem.
            Leaves – Opposite or whorled, simple, aromatic, exstipulate, hairy.
            Inflorescence – Verticillaster or fascicles of axillary cymes or dense spikes.
            Flower – Bisexual, zygomorphic, hypogynous, often bilabiate.
            Calyx – Sepals 5, united, persistent.
            Corolla – Petals 5, united, bilabiate, imbricate.
            Androecium – Stamens 4, epipetalous, didynamous or 2.
            Gynoecium – Carpel 2, syncarpous, ovary 4-lobed, superior, 4-locular, ovule 1 in each loculus, placentation axile, style gynobasic, stigma bifid.
            Fruit – Schizocarpic carcerule, rarely drupe.
             4. COMPARATIVE SYSTEMATIC POSITION AND AFFINITIES:
            Majority of the taxonomists including Bentham & Hooker, Hutchinson, Cronquist, Takhtajan, etc. have placed this family under the order Lamiales.          
            The family Lamiaceae is considered closely allied to the Verbanaceae. The family also resembles with Boraginaceae in fruit characters but the position of the radicle sharply distinguishes them. In some minor characters the family also shows affinities with the Scrophulariaceae. The resemblance with Acanthaceae of Lamiaceae is largely superficial.
              5. ECONOMIC IMPORTANCE:
            1. The members of family Lamiaceae are important as the source of aromatic oils which are extensively used in various perfumes, flavor and pharmaceutical industries. The essential oil yielding plants are – Ocimum sanctum, O. basilicum, O. virdi, O. gratissimum, O.canum, Mentha ravens, M. piperitia, M. spicata, Salvia officinalis, Lavendula spp., Elsholtzia spp., Hyptis suaveolens, etc.
            2. Some members are cultivated as ornamental plants. Ornamental species of the family are – Coleus aromaticus, C. blumi, etc.
            3. Others have medicinal values. These are – Leucas aspera, Leonarus sibiricus, Cannabis sativa, etc.
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