In the course of investigation on the histochemical changes in the rat adrenal glandafter prolonged electrical stimulation of sciatic nerve, neurons were found in medulla.Their presence in the rat has been an unsettled problem in the literature. It order tobring out a better picture of the nerve cells, three more rats, all over 2 years old, werekilled for silver preparations including Cajals Ⅳ, Ⅵ, Ranson's and Willard's modifications.They were sectioned in series. The number of nerve cells and their way of groupingwere found to differ in different specimens, including those from the same individual.Occasionally nerve cells were located under the capsule and in the zona reticulosa. The innervation of adrenal cortex was another problem under investigation. Inthe Cajal's Ⅵ preparation the reticular fibers were not stained so that the nerve fibersand neurofibrils were clearly shown. From this preparation were found looped terminalboutons at the periphery of the cells in the zona reticulosa and zona fasciculata.