For his son sometimes known as Emil Jr., see Friedrich Gustav Carl Emil ErlenmeyerRichard August Carl Emil Erlenmeyer, known in his own day and subsequently simply as Emil Erlenmeyer (28 June 1825 – 22 January 1909), was a German chemist known for contributing to the early development of the theory of structure, formulating the Erlenmeyer rule, and designing the Erlenmeyer flask, a type of chemical flask, which is named after him.