The indusium griseum, (supracallosal gyrus, gyrus epicallosus, dorsal hippocampal continuation) [1] consists of a thin membranous layer of grey matter in contact with the upper surface of the corpus callosum and continuous laterally with the grey matter of the cingulate cortex and inferiorly with the hippocampus.

It is vestigial in humans and is a remnant of the former position of the hippocampus in lower animals.

[4] The indusium griseum and fasciolar gyrus are very small components of the limbic lobe, and are continuations of the hippocampal formation, forming an unremarkable thin continuous ring of grey matter at the edge of the cortex.

[4] Toward the genu of the corpus callosum it curves down along the rostrum to form the subcallosal gyrus.

[5] This article incorporates text in the public domain from page 827 of the 20th edition of Gray's Anatomy (1918)