Crus of fornix

The crura (posterior pillars) of the fornix are prolonged backward from the body.

They are flattened bands, and at their commencement are intimately connected with the under surface of the corpus callosum.

Diverging from one another, each curves around the posterior end of the thalamus, and passes downward and forward into the inferior cornu of the lateral ventricle.

Here it lies along the concavity of the hippocampus, on the surface of which some of its fibers are spread out to form the alveus, while the remainder are continued as a narrow white band, the fimbria hippocampi, which is prolonged into the uncus of the hippocampal gyrus.