=====Median sulcus=====
The [[rhomboid fossa]] is divided into symmetrical halves by a median sulcus which reaches from the upper to the lower angles of the fossa and is deeper below than above. On either side of this sulcus is an elevation, the [[medial eminence]], bounded laterally by a sulcus, the sulcus limitans.

The median sulcus divides the floor into symmetrical halves. Each half is again divided into a medial eminence and a lateral area by the sulcus limitans.

{{:facial_colliculus.jpg|}}

[[Floor of the fourth ventricle]]: fc: [[facial colliculus]]; ht: [[hypoglossal triangle]]; if: [[inferior fovea]]; me: [[medial eminence]]; ms: [[median sulcus]]; o: [[obex]]; sf: [[superior fovea]]; sl: [[sulcus limitans]]; sm: [[medullary striae of fourth ventricle]]; vt: [[vagal triangle]].

{{::areapostrema.jpg|}}

Ap: [[area postrema]]; icp: [[inferior cerebellar peduncle]]; lr: [[lateral recess]]; ms: [[median sulcus]]; scp: [[superior cerebellar peduncle]]; sf: [[superior fovea]]; sm: [[Medullary striae of fourth ventricle]].