The authors present a histological study of the formation of the corpus luteum after follicular rupture. According to the classical conception, the corpus luteum is derived from luteinisation of the granulosa cells: the theca interna participates in its formation only to a lesser degree. The authors criticize this histogenesis and describe the corpus luteum as being entirely derived from thecal cells. Large and small luteal cells are all derived from mesenchymal elements of the ovarian stroma, which are the precursors of steroid-secreting cells. According to the authors, granulosa cells derived from the primary sex cords of coelomic mesothelial origin only play a support role for the oocyte. After expulsion of the oocyte from the dominant follicle, the granulosa cells which remain in the follicular cavity disappear without a trace.