Letter hand written by Pierre Rayer dated 1862. Rayer was a member of the Académie de Médecine and the Académie des Sciences, and co-founder of the Société de biologie, of which he was also president. He was a consultant-physician to King Louis-Philippe as well as Napoleon II. He made important contributions in the fields of pathological anatomy, physiology, comparative pathology and parasitology. Obo for quick sale