During the long years I was engaged in writing my “Mikrographie” (1), my main purpose was to give a survey of the wood-anatomy of as many representatives of the javanesc wood flora as I could lay hands on, in connection with Koorders’ and Valeton’s “Bijdragen” (2). My attention being almost exclusively absorbed by the descriptive side of my task, little attention was paid to eventual conclusions regarding family relationships, though some were incidentally pointed out. When this work of long years was completed, the need of a key for the identification of wood samples was felt. This I composed and completed just before the war. It was published in 1940 and written in German (3), as was the main work on which it was based. Immediately an English translation was prepared but though this was ready for the press as early as 1942, I was prevented from publishing it, at first because of the German occupation and later on for want of funds.