The pons is inferior to the mesencephalon. It is a portion of the brainstem. The pons rest upon the posterior surface of the body of the sphenoid bone and the upper part of the basilar process of the occipital bone. The pons is composed chiefly of white matter. It is located in front of the medulla oblongata and between the hemispheres of the cerebellum. It is about twenty-five millimeters long. It is convex from side to side. It has an anteroposterior median groove which accommodates the basilar artery. It consists primarily of two types of fibers: transverse (superficial) and longitudinal (deep) fibers. The transverse fibers extend laterally into each hemisphere of the cerebellum, forming the middle cerebellar peduncle. The longitudinal fibers extend forward and outward and help form he crura of the cerebrum. The upper surface of the pons forms a part of the floor of the fourth ventricle of the brain.

Pons Varolii

Pont