Alfred Kohn (1867–1959) was the head of the Institute of Histology at the Medical Faculty of German University in Prague for 26 years. He entered the history of medicine by discovery of the nature and origin of parathyroid glands and by pioneering research into chromaffin cells and sympathetic paraganglia. Kohn's papers on the pituitary, interstitial cells of testes, and ovaries are also related to endocrinology.