Falx cerebelli

The falx cerebelli is a small triangular process of dura mater, received into the posterior cerebellar notch.

Its base is attached, above, to the under and back part of the tentorium; its posterior margin, to the lower division of the vertical crest on the inner surface of the occipital bone.

As it descends, it sometimes divides into two smaller folds, which are lost on the sides of the foramen magnum.