Gynoecial ontogeny inEnicostemma littorale Blume

The gynoecial development inEnicostemma littorale Blume (Gentianaceae) has been studied. The bicarpellary, syncarpous gynoecium begins its development in an apocarpous fashion. The free carpels of the young gynoecium remain open and resemble those ofMichelia champaca, Polyalthia longifolia andCananga odorata studied earlier. The young carpel exhibits initial abaxial overgrowth followed by expansion of the adaxial surface while the laminai part develops. The marginal meristem continues to be active and proliferates into a much folded structure (the placenta) on which numerous ovules arise. The two carpels fuse by their margins and form the unilocular syncarpous gynoecium with parietal placentation. This postgenital fusion is initiated by the contact of the abaxial protodermal layers of the adjacent margins. The homologies of the carpel and gynoecium are discussed in the light of recent views on the nature of the gynoecium.