1. The first oxyntic cells, differentiating from a non-mucoid cell, appear on the 23rd day of the foetal life of the rabbit.
2. Bowie-positive granules appear in most epithelial cells during foetal life, reach a maximum on the 27th day, and then almost disappear before birth.
3. The first peptic cells containing Bowie-positive granules appear a few hours after birth. They increase after the end of the first week until the adult condition is reached.
4. During the first 4 weeks of postnatal life the pepsinogen granules contain a mucinogen component. This is lost between the fourth and sixth weeks. The loss starts in cells at the base of the glands and proceeds up the tubules towards the crypts.
5. Pepsinogen granules containing a mucinogen component are strongly eosinophil.
6. The first ‘mature’ peptic granules, that is ones that are Bowie-positive, PAS-negative and non-eosinophil, appear at the fourth week of postnatal life.
7. Mucous neck-cells (of Bensley) begin to appear at the end of the sixth week of postnatal life. Their development is being further investigated.