If the anther and stigma are placed at different positions in a bisexual flower to encourage cross-pollination, the contrivance is called

Alignment of androecium and gynoecium at different heights or positions in a bisexual flower is called herkogamy. Maturation of androecium and gynoecium at different periods in bisexual flower is called dichogamy. Production of unisexual flowers in a plant is called unisexuality of dicliny. Development of flowers with different heights of styles in different flowers of the same plant or species is called heterostyly.