The Mar. and May numbers of v. 97, 1930, combined in one issue, compromise a special series of articles on the Belgian Congo (Le Congo Belge et les sciences) published on the occasion of the centenary of Belgian independence. A separate map (Carte administrative du Congo Belge et de ses voies de communication) accompanies this combined issue, and is designed as "supplément à la Revue des questions scientifique, mars-mai 1930."