SUMMARY. — At first blush Louis Blaringhem (1878-1958) led the typical career of a French biologist under the Third Republic. A closer study of his biography reveals, however, an original personality. Initially cautious about the new approach to genetics that emerged after the rediscovery of Mendel's laws, Blaringhem later became one of the first teachers to teach Mendelian genetics in France. Blaringhem's biography is representative of the history of French genetics in the early 20th century. It not only epitomizes the resistance of the French neolamarckian community toward Mendelian genetics, but also sheds new light on the reception of Mendelism in France. Indeed, on the one hand, Blaringhem's early scientific work was deeply imbued with...