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Further observations on the floral morphology and anatomy of the monotypic genusMedusagyne from the Seychelles are presented. The unique synovarious gynoecium is composed of numerous carpels that are attached to the side of a broad, elongated torus. The biovulate carpels are differentiated into a narrow ovary, a stout, erect, three-trace style, and a lobed, discoid stigma. The carpel wall is initially composed of thin-walled parenchyma, but at later stages of development the peripheral region becomes subdivided into many lignified sterile extensions. Carples show pronounced ontogenetic adaxial deformation, during which the upper ventral surfaces become expanded, greatly extending the ventral margins and forming a domelike cushion of carpel-derived tissue over the summit of the torus. The distal cushion remains separated from the flattened torus by a compressed cavity and eventually undergoes lignification, perhaps protecting the underlying gynoecium from chewing insects and exposure. Comparisons are made between the mature gynoecia ofMedusagyne and those of the genusDillenia. The occurrence of S-type sieve-element plastids inMedusagyne is reported for the first time, a feature in agreement with suggested thealean affinities of the family.

A comprehensive study of floral and vegetative anatomy of the monotypic New Caledonian genusStrasburgeria Baillon was undertaken to provide a more thorough and accurate generic description, and to help clarify the evolutionary relationships of the plant. Detailed descriptions of leaf, stem, nodal, wood, floral, fruit, and seed morphology and anatomy are presented. In general, vegetative characters are primitive whereas those of the reproductive organs are regarded as advanced or specialized.Strasburgeria is envisioned as an early and independent offshoot from the thealean ancestral stock. It appears that the most appropriate treatment of the genus is to recognize the family Strasburgeriaceae and put it adjacent to the Ochnaceae in the current widely accepted manner.

A study of the floral anatomy and pollen morphology of both species of the endemic New Caledonian genusOncotheca was undertaken to provide a more thorough and accurate generic description and to make additional comparisons of the two species. In general, flowers of the species are histologically similar, althoughO. macrocarpa has a strong tendency to possess more numerous and widely distributed tanniferous cells and druses.Oncotheca macrocarpa also differs fromO. balansae in possessing the important feature of unfused ventral carpellary bundles. The unspecialized, 3-colporate pollen type of the two species is very similar in size and surface pattern, has clearly delineated wall layers, and is in harmony with the recent consensus opinion thatOncotheca is most closely related to the Theaceae and allies, although the genus is probably best interpreted as an isolated taxon linking the orders Theales, Ericales, and Celastrales.