The depressed area between the crura is termed the interpeduncular fossa, and consists of a layer of gray matter, the<unk> , which is pierced by small apertures for the transmission of blood vessels; its lower part lies on the ventral aspect of the medial portions of the tegmenta, and contains a nucleus named the interpeduncular ganglion; its upper part assists in forming the floor of the third ventricle.
Posterior perforated substance
Cecal bascule
Inoculum
Tight hymenal ring
Pocock boundary
Kronig isthmus
Orgasmic platform
Nodule of vermis