The post–embryonic development of the digestive gland has been studied by light and electron microscopy on animals reared in the laboratory. The gland reaches its “adult” structure around the end of the first month after hatching.

The infrastructural changes of the digestive gland have been followed during digestion at various ages (5,10,20,30 days and “adult”); ferritin was used for a tracer to study absorption.

These experiments have produced evidence of endocytosis intake of large proteins and further intracellular digestion inside the digestive cell. The residues of digestion are excreted in a “brown body” while the metabolites are used in new syntheses for the cell itself. These results demonstrate that “ancestral” digestive processes have been kept in at least one cephalopod.