[A generalized form of the Bertalanffy functions of organic growth (author's transl)]

A historical review of the derivation of the Bertalanffy functions of lenght and mass growth (1934) with a critical evaluation of the concept is given. After extending the development to a surface growth function a generalization of the 3 formulas based on critical ideas of Bertalanffy is established giving room for intermediate growth behaviour. Finally the properties of the generalized function are presented, and the limits of application illustrated with the aid of graphs.