Material and MethodsThe chief material used in this research is the endosperm cells of the castor bean (Ricinus communis) and some other oily seeds, e.g. the cotyledonary cells of soja bean (Glycine sofa.).The sections of the material were treated with osmium vapour and brought into glycerine or liquid paraffin in which the processes of the denaturation of the so-called protein crystal and the separation of oil from the crystal were observed.The development of the seeds and the aleurone grains in the cells mostly in the endosperm, was traced in the living materials. Osmium vapour or Sudan III was used generally for the test of oil, and Millon's reagent among others for the test of proteins and Fehling's solution for the test of reducing sugar.Observation