Lateral part of middle cranial fossa and posterior cranial fossa are divided by:

The interior of base of skull is naturally divided into 3 fossae Anterior cranial fossa Middle cranial fossa Posterior cranial fossa Lesser wing of sphenoid with anterior clinoid process divides anterior and middle cranial fossa. Petrous temporal bone separates the lateral part of middle cranial fossa from posterior cranial fossa. Dorsum sellae of sphenoid bone with posterior clinoid process separates the median part of middle cranial fossa from posterior cranial fossa.