Superior Perspective of the Cerebellum, Midbrain and Thalamus.  On the superior surface of the cerebellum, note that the anterior segment of the quadrangular lobule is located in the anterior lobe, and the posterior segment of the quadrangular lobule is located in the posterior lobe.  The two lobes are separated by the primary (preclival) fissure.  The superior posterior fissure divides the posterior quadrangular lobule (also referred to as the simple lobule) from the superior semilunar lobe. The superior semilunar lobule is separated from the inferior semilunar lobule by the horizontal fissure. Rostral to the cerebellum can be seen the tectum (superior and inferior colliculi) of the midbrain.  Further rostral still, the lateral ventricles have been opened bilaterally to expose the thalamus and caudate nucleus within the floor of the ventricle, and the interventricular foramen of Monro.  On the left side, a prominent tuft of choroid plexus runs along the floor of the ventricle dorsal to the thalamus and continues into the foramen of Monro.   (Image courtesy of AL Rhoton, Jr.)