Nature and development of plants . pels, as is indicated by the two stig-mas and two rows of ovules (Fig. 308, C). The stigmas arereceptive as soon as the flower opens, but the anthers remainclosed, and so the spores must be carried from an older petals close during the late afternoon and when opened on DEVELOPMENT OF PLANTS 411 the following day the anthers shed their spores and complete theflowering. In higher types of the poppies we find the flowers becomingirregular and the various parts reduced in numbers. Thus, inthe soldiers cap (Fig. 308, D), there are two scale-like sepals,
Nature and development of plants . pels, as is indicated by the two stig-mas and two rows of ovules (Fig. 308, C). The stigmas arereceptive as soon as the flower opens, but the anthers remainclosed, and so the spores must be carried from an older petals close during the late afternoon and when opened on DEVELOPMENT OF PLANTS 411 the following day the anthers shed their spores and complete theflowering. In higher types of the poppies we find the flowers becomingirregular and the various parts reduced in numbers. Thus, inthe soldiers cap (Fig. 308, D), there are two scale-like sepals,four petals in two pairs, the two outer heart-shaped and spurredat the base, while the two inner are narrow and winged on theback, enclosing the sporophylls. The six stamens are somewhatunited and arranged into two groups opposite the spurred carpel has the same structure as in the bloodroot. It isevident that the nectar concealed in this closed type of flowercan only-be secured by some long-tongued insect. Find out how. Fig. 308. Examples of the poppy family, order Papaverales: A, habitof the bloodroot at time of flowering—r, rhizome; /, leaf folded aboutflower stalk. B, leaf unfolded. C, section of flower, showing its hypo-gynous structure with numerous stamens and pistil of two carpels. D,flower of fumitory (Adhtmia)—s, sepal; />, inflated petals; w, wingedpetals which conceal the sporophylls. 412 THE PAPAVERALES the bee procures the honey, the purpose of the wings on thenarrow petals and the position of the nectar glands. Is thestigma mature before the anthers open? The structure of thishigher type of the poppies makes the transition to the mustardfamily a simple one. (b) The Mustard Family, Crucifcrae.—Here we find thesepals and petals four in number, and the latter arranged cross-wise (Fig. 309, A, B), thus explaining the family name, Crucif-erae. The petals usually have rather long claws (Fig. 309, D)
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