1. The wall of the posterior horn of the lateral ventricle of brain (rabbit), lined by the Radiatio corporis callosi and the Alveus, is covered with a simple cuboidal ependyma.

2. It develops as a thickening of the ependyma around the pineal recess of the third ventricle and is attached by peduncles to the habenular and posterior Commissures (Kappers, 1981; Korf et al., 1998).