The development of inflorescences and flowers of the African Oil Palm up to anthesis is illustrated by scanning electron microscopy images. The time of origin relative to the development of the foliage leaves of the basipetalous succession of flowering rachillae is determined, as well as the time of morphological sex definition. The logical stage when sex is determined is inferred to be not before the first appearance of the spikelet primordia. Female flower groups develop acropetally as triaxial cincinni, the male units as reduced ones. A developmental diagram is added