It seems that the particular intermediary disposal of zona fasciculata in the cortical ensemble of the adrenal gland is not insignificant, especially for the variability and for the glandular activities. Because of its specific cellular arrangement, displaying both positional and dimensional uniformity; it can be considered like a real islet of orderly cordonal symmetric tissue between two other cortical zones which present instead a very irregular cellular disposal. Distinct capsular fibrillar elements inserted around the cells and especially around small calibre vascular structures from zona fasciculata, are directly involved in the distribution of the secretory products. The concentration of the lipidic components is always more important at this cortical level than anywhere else in the whole adrenal gland, probably in connecting with the microsystem of channels from the entire surface of the zona fasciculata cells.