B. Unpaired bones of the braincase

2. Occipital

The occipital bone is formed by paired exoccipitals, a supraoccipital and a basioccipital. The dorsolateral borders form the nuchal crest at the junction with the parietal and the temporal bones. The external occipital protuberance is formed dorsally in the middle between the nuchal crests, where the interparietal fused with the occipital. The brain stem exists the cranial cavity through the large foramen magnum.

The hypoglossal canal passes through the ventral part of the occipital bone. It provides passage for the hypoglossal nerve.