Abstract
In the early embryonic stage the silk gland cells contain hardly any rough ER and ribosomes exist freely in the cytoplasm. A number of mitochondria are observed, some of which are probably in the process of fission. Since rough ER and Golgi apparatus are very poorly developed, it is suggested that secretory protein is not yet synthesized in the silk gland cells in this stage.
In contrast to the arrangemen t of the glandular cells in regular two rows at 24 hours after the blastokinesis, a number of cells exist irregularly around the glandular lumen in the early embryonic stage.