Pineal gland forms
Anterior wall :Anterior column of fornixAnterior commissureLamina terminalisPosterior wall:Pineal glandPosterior commissureCommencement of cerebral aqueduct.Roof: ependymaFloor:Optic chiasmaTuber cinereumMamillary bodiesPosterior perforated substanceTegmentum of midbrainLateral wall:ThalamusHypothalamusRef: Vishram Singh textbook of clinical neuroanatomy second edition pg 137
Brain 
Floor of third ventricle
Anterior wall of third ventricle
Posterior wall of third ventricle
Roof of third ventricle
Posterior wall of third ventricle