Staining properties of the luminal epithelium of the isthmus and shell gland of the oviduct of the hen Gallus domesticus during the passage of an egg

The effect of a developing egg on the staining properties of the luminal epithelium of the isthmus and shell gland of the oviduct of the hen Gallus domesticus is described, with special reference to the red region. Using histochemical methods for the demonstration of complex mucopolysaccharides, the staining reactions in the surface epithelium adjacent to an egg were found to be similar to those seen in an empty oviduct. With the empirical methods for intracellular calcium, a staining reaction was seen in cells which were adjacent to an egg. There was no reaction in an empty oviduct. If an egg lay between the red region and the shell gland, methods for the demonstration of acid mucopolysaccharides or intracellular calcium showed a more pronounced reaction in an area of surface cells at the neck of the shell gland. These results are based on recently defined anatomical regions.