Rathke's pouch
A pouch of ectoderm that grows out from the upper surface of the embryonic stomodeum and gives rise to the anterior and intermediate lobes of the pituitary gland[MP]. In embryogenesis, Rathke's pouch is a depression in the roof of the developing mouth in front of the buccopharyngeal membrane. It gives rise to the anterior pituitary (adenohypophysis), a part of the endocrine system[WP].