THE Colonial Office has issued the sixth annual report (1933-34) of the East African Research Station at Amani (London: H.M. Stationery Office. Is. net), from which it is evident that progress has again been made in all the various research activities with which the Station is concerned. As regards coffee investigations, the earlier impression that heavy applications of organic manures to arabica coffee effectively offsets the harmful influence of soil acidity has now been confirmed, while culture solution studies suggest a marked correlation between acidity of the medium and the degree of branching of the roots which occurs, high acidity being associated with an un-branched type of root system. Results of importance have also been obtained by the plant pathology section, as the vector of the mosaic disease of Cassava has been definitely proved to be a species of white fly (Aleurodidce). On the biochemical side comes the discovery that the fermentation of coffee is an unnecessary process so far as quality is concerned, though the difficulties of correlating quality with the method of preparation of the coffee are still not overcome. The cultivation of sisal (Agave amaniensis) continues to increase, and the first lot of seedlings raised at the research station are now becoming available for fibre tests, the standardisation of which has been considerably developed during the past year.