The Gynoecium and the Androecium
The functional reproductive parts of the flower are divided into the gynoecium (female) and the androecium (male). In practice, the gynoecium equates to the pistil plus the ovules, and the androecium to the stamens plus the pollen. The pistil (gynoecium) is in turn, made up of three component parts: the ovary, style and stigma. In the examples shown here, L. aestivum and F. meleagris, the stigmas differ in two important respects: the stigma of L. aestivum is much smaller than that of F. meleagris and it is not obviously subdivided, despite the ovaries of both species being sub-divided into three carpels. Also, L. aestivum has an inferior ovary, i.e. it lies outside the perianth; whereas the ovary of F. meleagris is superior, i.e. inside the perianth. The terms 'superior' and 'inferior' are widely interpreted as meaning 'above' and 'below' the perianth respectively. This is logical provided that the flower is upright; however, the flowers of many species, like the examples shown here, are pendulous, making the terms 'above' and 'below' ambiguous. Therefore 'inside' and 'outside' the perianth are used here as more precise and intuitive terms. In both these species, the style is elongated - particularly so in F. meleagris, which leaves the stigma close to the mouth of the perianth when the flower is fully open, and will make it available for both wind and insect pollination. The stamens (androecium) can be divided into the anther, which bears the pollen, and the filament which in turn bears the anther. The relative lengths of the filaments in these two species largely reflect the overall architecture of the flower, L. aestivum being a shallow, open flower compared with F. meleagris. The structure and function of the pistil and stamens are considered in greater detail on other pages.
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