The intrafamilial relationships of the Rubiaceae will be studied on the basis of wood anatomical characters. Observations and measurements of a selected number of wood slides will provide detailed descriptions and illustrations. Data from literature and own observations will result in a phylogenetic scenario. Aluminium accumulation in wood and leaves is also investigated within the Rubiaceae in order to determine the taxonomic significance of this character. Finally, the distribution and morphology of vestured pits is studied in flowering plants. A better knowledge of this feature is useful for phylogenetic studies.