In marginal placentation, placenta forms a ridge along the ventral suture of ovary. In sweet pea, marginal placentation is present. Basal placentation is present and develops at the base of the ovary and single ovule is present, e.g., sunflower, marigold.
In axile placentation, ovules are attached to the multilocular ovary.
Parietal placentation develop on the inner wall of the ovary or on the peripheral part.