In the axial skeleton of vertebrates, the bony structure that encases the brain. The cranium comprises three parts: dermatocranium; chondrocranium; and splanchnocranium. The dermatocranium includes the roof of the cranium, the area around the orbits, and the jaw. The chondrocranium includes the floor of the cranium. The splanchnocranium gives rise to the visceral skeleton (gill arches and derivatives such as larynx and trachea).