Exploration of the cerebellum and brain stem from above and behind
Rhomboid fossa of fourth ventricle
The tela chorioidea has been removed and the posterior parts of the cerebellum resected so that the floor of the fourth ventricle (the rhomboid fossa) can be seen. This fossa is divided into superior, intermediate and inferior areas which are not labelled in the drawing. The lateral recess lies opposite the intermediate area. Although the position of the obex (10) is indicated, no evident thickening of the pia mater was present in this specimen.
Anterior medullary velum
Median eminence
Dentate nucleus
Prominence in wall of ventricle produced by medial part of dentate nucleus
Medullary striae
Sulcus limitans (pointer on inferior fovea rhomboid fossae)
Hypoglossal trigone
Wing of gray matter (overlying dorsal motor nucleus nerve X)
Calamus scriptorius (dorsal median sulcus)
Posterior median fissure and obex
Inferior colliculus
Trochlear nerve (IV)
Median sulcus of rhomboid fossa
Superior fovea rhomboid fossa
Facial colliculus
Fibers from peduncle of flocculus ascending into tegmentum
Lateral recess of rhomboid fossa
Taenia fourth ventricle
Restiform body (inferior cerebellar peduncle)
"Funiculus separans"
"Area postrema"
Clava
Medullary substance of biventral lobule (ventral paraflocculus)