The nodule (nodular lobe), or anterior end of the inferior

vermis The cerebellar vermis (from Latin ''vermis,'' "worm") is located in the medial, cortico-nuclear zone of the cerebellum, which is in the posterior fossa of the cranium. The primary fissure in the vermis curves ventrolaterally to the superior s ...

, abuts against the roof of the

fourth ventricle The fourth ventricle is one of the four connected fluid-filled cavities within the human brain. These cavities, known collectively as the ventricular system, consist of the left and right lateral ventricles, the third ventricle, and the fourth ...

, and can only be distinctly seen after the

cerebellum The cerebellum (: cerebella or cerebellums; Latin for 'little brain') is a major feature of the hindbrain of all vertebrates. Although usually smaller than the cerebrum, in some animals such as the mormyrid fishes it may be as large as it or eve ...

has been separated from the

medulla oblongata The medulla oblongata or simply medulla is a long stem-like structure which makes up the lower part of the brainstem. It is anterior and partially inferior to the cerebellum. It is a cone-shaped neuronal mass responsible for autonomic (involun ...

and

pons The pons (from Latin , "bridge") is part of the brainstem that in humans and other mammals, lies inferior to the midbrain, superior to the medulla oblongata and anterior to the cerebellum. The pons is also called the pons Varolii ("bridge of ...

. On either side of the nodule is a thin layer of white substance, named the posterior medullary velum. It is semilunar in form, its convex border being continuous with the white substance of the cerebellum; it extends on either side as far as the

flocculus The flocculus (Latin: ''tuft of wool'', diminutive) is a small lobe of the cerebellum at the posterior border of the middle cerebellar peduncle anterior to the biventer lobule. Like other parts of the cerebellum, the flocculus is involved in moto ...

Additional Images

File:Slide2SEER.JPG, Cerebellum. Inferior surface. File:Slide3EER.JPG, Cerebellum. Inferior surface. File:Slide4SER.JPG, Cerebellum. Inferior surface.

External links

* * https://web.archive.org/web/20010514005529/http://www.ib.amwaw.edu.pl/anatomy/atlas/image_11e.htm Cerebellum {{neuroanatomy-stub