With astonishing diligence the thick third volume of this important work has been produced. Among the 79 families treated there are some large or very large ones, e.g. Anacardiaceae, Apocynaceae, Asclepiadaceae, Compositae, Cruciferae, and Cucurbitaceae. There is a general introduction for Dicotyledones, with a survey of phyletic affinities assumed by Takhtajan, Von Wettstein, and Hutchinson respectively, chemical characteristics of Dicots, alcaloid occurrence in Dicot. families, the occurrence of ‘pseudoindikanen’ and allied compounds, occurrence of salicyl compounds. After the family treatments, which are executed as in vol. 2, there is a fairly large amount of addenda to these families, and a large index. An analysis showed that of the 79 families treated the author says that 42 are distinctly insufficiently known phytochemically, and 17 are virtually unknown. As many of these two groups are very small, it would seem desirable that phytochemists decide to a joint effort to bring this up to date.