The official photograph includes but half of the 45 registrants at the Chicago Congress and excluded Macfarlane. Though he participated in later ICM's, his bid for inclusion in 1893 was blunted.
We see Felix Klein front and center and facing the camera in the official photo. It is Eduard Study, also representing Germany, positioned over his right shoulder, slouching in his seat, head slightly tilted. The other photograph has Macfarlane facing the camera, Henry Clew looking on.
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