[Demonstration by electron probe microanalysis and by ionic microanalysis, of nuclear localization of aluminium of various cells].

The presence of aluminium (A1) in the nuclei of thyroid cells (Rabbits), liver and skin cells (Frogs) and in the nucleolus of a Radiolarian is described. The possibilities of artifacts with these two histophysical methods are briefly discussed, and biological significance of this nucleic aluminium is evoked.