Median sulcus of the tongue

The dorsum of the tongue is convex and marked by a median sulcus, which divides it into symmetrical halves.

This sulcus ends behind, about 2.5 cm. from the root of the organ, in a depression, the foramen cecum, from which a shallow groove, the sulcus terminalis, runs lateralward and forward on either side to the margin of the tongue.