The convex superior pa of corpus callosum(dorsal) is covered by a thin layer of grey matter, the indusium griseum, embedded in which are the fibre bundles of bilateral medial and lateral longitudinal striae.Superiorly, it is also related to anterior cerebral vessels and cingulate gyrus.Ventrally, it is attached with the convex superior aspect of fornix by septum pellucidum. It is also related to lateral ventricle.(Ref: Vishram Singh textbook of clinical neuroanatomy, second edition pg 164, fig14.4)