Governed by forces such as these, and limited by competition with each other, plant species have for ages taken their places in the global economy and carried out their part of the commandment to be fruitful and multiply. Otherwise we and the animals we prey upon could not exist.
FLOWER FORMS
The four flowers sketched below with supplementary drawings of their separate parts, give only a small sample of the infinite structural variety found among flowering plants.
A Yucca, illustrating features which are found in several other lilies.
perianth segment stigma anther style ovary pedical stem Detail of stamen pollen anther filament
A Buttercup. This particular one has showy sepals but no petals.
group of styles sepal group of stamens ovary pedical single sepal Detail of stamen
