CYTOLOGY OF VITELLOGENIC STAGES OF OOGENESIS IN DROSOPHILA MELANOGASTER

The cytology of the vitellogenic stages in the development of the oocyte of Drosophila melanogaster has been studied using whole mounts and sections of plastic‐embedded ovaries and single egg chambers for light microscopy and cytochemistry. The migrations, changes in morphology, and synthetic products of the follicle cells are described as a function of developmental stage. The follicle cells synthesize the egg coverings, the vitelline and chorionic membranes, and elaborate the micropyle and dorsal chorionic appendages. The changing structure of the nurse cell nucleus and changes in organelle composition of its cytoplasm are described. The nurse cells synthesize ribosomes, lipid droplets, and mitochondria. These components pass through the ring canal system into the oocyte, which increases in volume some 200,000 times during its 78 hours of development. Copyright © 1969 Wiley‐Liss, Inc.