The basement membranes of the adenohypophysis and the diencephalon are in contact. The basement membranes of the adenohypophysis and the future infundibular area of the diencephalon are in contact however blood vessels begin to grow in between them. The notochord appears to be in contact with the adenohypophysis. An infundibular recess has finally appeared in the floor of the diencephalon adjacent to the adenohypophysis. In some embryos it remains in contact with the adenohypophysis, whereas in others the two are separated by mesenchyme.
All embryos have an infundibular recess extending into the neurohypophysis.
The wall of the adenohypophysis closest to the neural ectoderm is thickened. It is still in communication with the pharyngeal cavity. The walls of the neurohypophysis are folded. Fig 9E and closely apposed to the adenohypophysis which now retains only an epithelial cord connecting it to the oral cavity.