. The classification of flowering plants. Plants. LEGUMINOSAE 3o9 or shorter stalk, and often girt at the base by a hypogynous nectar-secreting disc. In the second and third subfamiHes the zygomorphy of the flower is often expressed in the terminal style by a difference between back and front, and a well-marked bending; more rarely is it straight, or rolled as in Phaseolus. Departures from a monocarpellary pistil are rare. Toiinatea dicarpa (Caesalpinioideae) has two carpels, while in several genera of the tribe Ingeae (Mimosoideae) there are more than one. Occasionally the number of ovules is
. The classification of flowering plants. Plants. LEGUMINOSAE 3o9 or shorter stalk, and often girt at the base by a hypogynous nectar-secreting disc. In the second and third subfamiHes the zygomorphy of the flower is often expressed in the terminal style by a difference between back and front, and a well-marked bending; more rarely is it straight, or rolled as in Phaseolus. Departures from a monocarpellary pistil are rare. Toiinatea dicarpa (Caesalpinioideae) has two carpels, while in several genera of the tribe Ingeae (Mimosoideae) there are more than one. Occasionally the number of ovules is reduced; some species of Trifolium and Medicago have only one. The ovules are amphitropous or anatropous, some- times campylotropus. and obliquely ascending or pendulous, with one or two integuments; the number varies even in the same Fig. 181. Floral diagrams of A, Vicia Faba; B, Laburnum vulgare; C, Amorpha fruticosa; D, Chorizema cordatum, (After Eichler.) In Mimosoideae and Caesalpinioideae the stamens and stigma are freely exposed and the stamens as well as the petals serve to attract insects. Frequently, as in Mimosa, the flowers are massed in heads. The relation of insects to the flower has been carefully studied only in Papilionatae, and chiefly in European species. H. Milller has described the structure of the flower and its pollination in numerous species. In nectar-containing species nectar is secreted from the inner sides of the bases of the filaments and accumulates round the base of the ovar^^, hing at the bottom of a tube formed by the filaments of the stamens and rendered more rigid by the claws of the petals and the stiff, more or less tubular, calyx. It is accessible therefore onl}' to an insect Avith a long proboscis, and observation shews that Papilionatae are essentially bee-flowers. In such species the posterior stamen is free and a passage to the nectar is made by an arching outwards of its base or of the bases of the adjoinuig filaments on eithe
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectplants, bookyear1904
