The most characteristic feature of this group is the skull structure.

Cartilaginous fish, such as sharks, have also simple, and presumably primitive, skull structures.

Turtles have been traditionally believed to be surviving anapsids, on the basis of their skull structure.

"It is very beautiful and it has a long skull structure."

The skull structure of both snakes and lizards is distinctive.

The skull structure of Platecarpus is unique among mosasaurs.

Once this man's ancestors must have been purebred Manchu, for he had the long, high-domed skull structure peculiar to them.

"You've got a different skull structure from other Psychlos," said Jonnie.

He also studied skull structure, such as the shape of the chin and cheekbones.

That was changed due to them retaining the vestigial reptilian jawbones and a different skull structure.