FLOWER OVARY POSITION
The location of the ovary, in relation to the other flower parts, is a key feature used to identify a flower species. It is thought that the earliest flowers to evolve had superior ovaries but the need to protect the ovary and fruits from pollinators led to the development of inferior ovaries or the hypanthium (a cup-shaped extension of the receptacle, which encloses the ovary). The flower ovary position is illustrated by the three examples shown below.
This photo shows a Superior ovary. The sepals, petals and stamens arise from below the ovary.This is the commonest type of ovary. The flower is technically Hypogynous where hypo means flower parts start ‘below’ the ovary. This is the flower of a geranium.
This photo shows an Inferior ovary. The tepals, corolla tube and stamens (filaments plus anthers) arise from above the ovary. The flower is technically Epigynous where epi means ‘above’. This is the flower of a daffodil.
This photo shows a type of Superior ovary that appears to be Inferior. The flower parts arise from the rim of a hypanthium – a cup shaped extension of the base which encloses the ovary. Imagine the hypanthium to be a flat ring and you can see that the flower parts actually arise from below the ovary. The flower is technically Perigynous where peri means ‘around’. Typical of the Rose family. This is the flower of a wild cherry.