In the preface to Part I of this volume, which appeared in 1966, we stated: " ... we had to leave the Antihistaminics for another volume of unpredictable dimensions. In 1924, eight pages inserted in a Chapter on Mutterkorn by Arthur R.Cushing were considered enough, in Vol. II, Part II, pp. 1319-1326 of the Hand- buch. Now 922 pages did not suffice to cover all aspects of the subject ... the subject has been expanded in so many directions, that the anti histaminic part had to be excluded from the present volume. Possibly, another thousand pages will be necessary to cover what remains of the...