["Preformation and prediction" of the human sex. Wilhelm Weinberg's critique of Otto Schöner's "theory"].

In 1909 Otto Schöner, a district medical officer, claimed human sex to be determined by ovarian preformation and to be precisely predicted. Up to his death in 1940 Schöner denied not only the role of sex chromosomes, but chromosomes as carrier of heritage in general. His "theory" of sex preformation in the human ovary and sex prediction was published in renowned journals, e.g. "Zentralblatt für Gynäkologie" and "Zeitschrift für Geburtshilfe und Gynäkologie". His statistics as well as the "theory" were criticized by Wilhelm Weinberg, a general practitioner, obstetrician and statistician. Weinberg's name has been firmly linked to a principle of population genetics by the eponym "Hardy-Weinberg-law". This paper is intended to give an extensive description of the controversy between Schöner and Weinberg.