1.
canal for tensor tympani muscle
2. auditory tube
3. internal carotid artery
4. facial nerve
5. geniculate ganglion
6. greater petrosal nerve
7. lesser petrosal nerve
8. promontory formed by 1st turn of cochlea
9. tympanic plexus
10. round window
11. lateral semicircular canal
12. facial canal and facial nerve
13. oval window for stapes
14. tympanic nerve from IX
15. jugular vein
16. opening to mastoid air cells (aditus ad antrum)
17. tendon of stapedius muscle
18. malleus
19. tympanic membrane
20. chorda tympani
21. stylomastoid foramen