Pineal recess
Encyclopedia
The pineal recess is a small recess of the third ventricle
which projects into the stalk of the pineal body.
Third ventricle
The third ventricle is one of four connected fluid-filled cavities comprising the ventricular system within the human brain. It is a median cleft between the two thalami, and is filled with cerebrospinal fluid ....
which projects into the stalk of the pineal body.