Position of floral parts on thalamus in respect to
ovary:
Based on this flower are of three types:
1.Hypogynous
2.Perigynous
3.Epigynous
Hypogynous flower : The upper part is swollen & disc shape ,Gynoecium is situated above the thalamus & other flower parts like calyx corolla and androecium arise below the level of ovary. Hence ovary is superior in this case. Ex. Citrus , Brassica
Perigynous: Thalamus may be disc shaped ,cup shaped or flask shaped . Gynoecium is placed at the bottom of the cup and other floral parts androecium calyx corolla arises around the ovary not beneath it hence ovary is half superior. Ex. Rose
Epigynous: Thalamus is usually flask shaped or tubular . Calyx corolla and androecium born on the upper part of thalamus above the level of the ovary . Ovary is completely enclosed by thalamus and its walls are fused with thalamus .Ovary is inferior in this case .Ex. Cucurbita.
