Richet, Charles Robert (shärl rōbĕr` rēshā`), 1850–1935, French physiologist. From 1887 to 1927 he was professor at the Univ. of Paris. His special study was anaphylaxis, a term he used to describe a phenomenon noted earlier by Theobald Smith, i.e., a hyper-sensitive reaction (akin to allergy) to injections of foreign proteins, e.g., serums. For his work on anaphylaxis he received the 1913 Nobel Prize in Physiology or Medicine. He also worked on serum therapy, the nervous system, and animal heat and was interested in psychical research. Richet discovered that hydrochloric acid is the base of gastric juice.