A collective abstract dealing with the role of the ergastoplasm, mitochondria and Golgi material in secretion. Bowen concludes that "Secretion is in essence a phenomenon of granule formation." The granule arises as a minute vacuole in the Golgi area, "and the evidence indicates, if it does not demonstrate, that the primordial vacuole arises through the activity of the Golgi substance. Apparently the Golgi apparatus plays some immediate role in the process of accumulation and final synthesis of the secretion product, but the concomitant changes in other cellular structures suggest that all parts of the cell contribute in some way. This very probably means that the chon-driosomes (and ergastoplasm, if any) are concerned in some indirect manner which is not registered in their morphologic history; and further that the nucleus cooperates in some way with the cytoplasmic area. . . .".