The Posterior inferior aspect of the cerebellum and brain stem
Foramen of Magendie
The right cerebellar tonsil has been removed from this specimen without disturbing the meninges related to its inner surfaces. The tela chorioidea (11) forms the posterior part of the roof of the fourth ventricle and borders a large opening inferiorly, the foramen of Magendie, which forms the communication between the ventricle and the cerebellomedullary cistern (cisterna magna). Two folds of choroid plexus which lie in the roof of the ventricle can be seen through the foramen. The right posterior inferior cerebellar artery is incompletely filled with red latex.
Arachnoid membrane at border of cerebellomedullary cistern (cisterna magna)
Tonsil (ventral paraflocculus)
Postpyramidal fissure (fissura secunda)
Clava
Transverse cerebellar fissure
Accessory nerve (CN XI)
Dorsal root cervical nerve II
Uvula (vermis)
Posterior inferior cerebellar artery left
Medullary substance of tonsil
Tela chorioidea fourth ventricle
Medial aperture fourth ventricle foramen of Magendie