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Open- and hand pollination, ovule morphology, seed structure and germination of Gloriosa superba L. are discussed as possible factors influencing reproduction. The protogynous flowers in the frondose raceme are psychophilous and ornithophilous with a stigma receptivity period of at least four days. Development of the femaie gametophyte conforms to the Polygonum type, The inner integument acts as an endothelium due to the absence of the nucellus on the lateral sides of the embryo sac, where the nucellus has degenerated. A well-developed funicular obturator directs pollen tubes to a nucellar epistase where a partial self-incompatibility reaction appears to occur. A hypostase on the chalazal side contains transfer cells connecting the vascular tissue with the embryo sac. Seeds are tegmic, surrounded by a sarcotesta showing adaptations for endozoochory. Seed production was slightly better after cross-pollination, and also when 4B hour-old pollen was used, especially when pollination was done in the second flower phase. When the three factors were combined and applied to the proximal flowers in the inflorescence, seed production was significantly improved.

The structure of the pistil exudate, transmitting tissue and pollen tube growth of Gloriosa superba L. were studied. Flowers are protogynous, as the stigmas become receptive one day prior to anther dehiscence, and remain receptive for at least four days. Neutral red and auramine O proved to be useful for the indication of stigma receptivity. The stigma is wet while the papillae and canal cells form slight interior cell wall ingrowths reminiscent of transfer cells. Pistil exudate is mostly lipidic, confirmed by the prevalence of endoplasmic reticulum in the cytoplasm. The canal exudate includes substances derived from degenerating canal cell walls and lipid-like vesicles breaking down into fine fibrillar matter possibly associated with the pollen tube cell wall. Pollen tubes grow in close association with the stylar secretion, reaching most ovules, even though pollen tube numbers decrease on their way down the stylar canal. Callose deposition in the nucellus of some self-pollinated ovules could be indicative of a partly pre-zygotic gametophytic self-incompatibility system.