Of these, one of the largest is the parasphenoid which, in Ichthyopsids, is found underlying the basicranial axis.
In front of the presphenoid the basicranial axis is continued by the mesethmoid.
The posterior part of the craniofacial axis, which has relations only with the cranium, is called the basicranial axis.
In the Cervidae and Giraffidae the face is not bent down on the basicranial axis as it is in the Bovidae.
The basicranial axis is straight, and the fontanelle in the lachrymal region is very large.
Some of the most important structural features that mark it as such are in the basicranial region.