. Handbook of flower pollination : based upon Hermann Mu?ller's work 'The fertilisation of flowers by insects' . Fertilization of plants. CRUCIFERAE 117 agi. B. laevigata L. (Herm. Miiller,' Alpenblumen,' pp. 148-9.)—The flowers are aggregated into conspicuous inflorescences. Outside the base of each short stamen there is a nectary, the secretion of which collects in the cavity of the sepal immediately below it. There is a non-secreting nodule outside the base of each pair of long stamens. Each petal possesses a basal lobe each side, the one on the side next the short stamen being considerably
. Handbook of flower pollination : based upon Hermann Mu?ller's work 'The fertilisation of flowers by insects' . Fertilization of plants. CRUCIFERAE 117 agi. B. laevigata L. (Herm. Miiller,' Alpenblumen,' pp. 148-9.)—The flowers are aggregated into conspicuous inflorescences. Outside the base of each short stamen there is a nectary, the secretion of which collects in the cavity of the sepal immediately below it. There is a non-secreting nodule outside the base of each pair of long stamens. Each petal possesses a basal lobe each side, the one on the side next the short stamen being considerably larger than the other, and thus serving as a nectar-cover for the functional nectaries, leaving free but a small passage to the secretion. The reduction of the other lobes of the petals is correlated with the vestigial condition of the remaining nectaries. The anthers are so placed that every insect approaching the nectar must on three sides touch a dehisced anther, and on the fourth come into contact, with the simultaneously mature stigma. An insect passing from flower to flower will therefore continually eff'ect cross-pollination. Failing insect-visits, the anthers and stigma are. Fig. 35. Biscuielia laevigata^ J^. (after Henn. Miiller). A. Flower after removal of two sepals and two petals: seen from the side. B. Petal seen from the inner side. C. A short stamen with the two adjacent petals (x 7). a, one of the lower sepals with a cavity {b) in its base, which serves as a nectar reservoir; c, functional nectary; d, vestigial nectary ; e, the two short stamens, which dehisce introrsely ; yi the four long stamens, which dehisce towards the short ones; £, one of the upper sepals; k, petals; /, ovary ; k, style ; /, stigma ; jn, larger lobe of a petal; «, smaller lobe of a petal; 0, entrance to the nectar. brought into contact by the closing of the flower, so that automatic self-pollination ensues. Visitors.—Herm. Miiller observed 23 flies, 5 Hymenoptera, 6 Lepidoptera, an
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