External base of the cranium
| Term name | Layer | |
|---|---|---|
| 1 | Incisive canals | Layer 1 |
| 2 | Greater palatine canal | Layer 1 |
| 3 | Choana; posterior nasal aperture | Layer 1 |
| 4 | Petrosphenoidal fissure; sphenopetrosal fissure | Layer 1 |
| 5 | Petro-occipital fissure | Layer 1 |
| 6 | Foramen lacerum | Layer 1 |
| 7 | Lesser palatine canals | Layer 1 |
| 8 | Bony palate | Layer 1 |