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 the envelopes are pushed downward and outward and the pistil and stamens come in contact with its abdomen. Since the flower is proterandrous, the pollen that the pistils receive from the bee's abdomen must come from another flower. Note a somewhat similar arrangement in the toadflax or butter-and-eggs.

, surrounding the pistils.

In some cases (Fig. 203) the stamens are longer than the pistil in one flower and shorter in another. If the insect visits such flowers, it gets pollen on its head from the long-stamen flower, and deposits this pollen on the stigma in the long-pistil flower. Such flowers are dimorphous (of two forms). If pollen from its own flower and from another flower both fall on the stigma, the probabilities are that the stigma will choose the foreign pollen.

Many flowers are pollinated by the wind. They are said to be anemophilous ("wind loving"). Such flowers pro-