 Currently, this term refers to this separate cell mass in the caudal portion of the dorsal diencephalon, known as the epithalamus, found in all vertebrates on both sides of the third ventricle.It is embedded in the posterior end of the stria medullaris from which it receives most of its afferent fibers.By way of the fasciculus retroflexus (habenulointerpeduncular tract) it projects to the interpeduncular nucleus and other paramedian cell groups of the midbrain tegmentum.