What does a nude photograph by Wilhelm von Gloeden have to do with drawings of extracted genitalia? What connects the studio photography of a 'mannish woman' against a romantic backdrop with the multi-columned table of sexual intermediates? Or the artistic anatomy of the anthropologist Gustav Fritsch with the X-ray of a pelvis that Rudolf Virchow had for examination? Iconographically and media-technically, not much; epistemologically, a great deal. Within the procedures that aimed to determine what gender is and how it manifests around 1900, countless images were circulated. However, at times, not only the indeterminacy of gender became apparent, but also the ambiguity of the images themselves.