has part has part has_part characteristic of has modifier abnormal pituitary diverticulum morphology small Rathke's pouch reduced size of the pouch of ectoderm which grows out from the upper surface of the embryonic stomodeum and gives rise to the anterior and intermediate lobes of the pituitary gland decreased Rathke's pouch size reduced Rathke's pouch size MP:0013349 abnormal decreased size Rathke's pouch