The two major cavities are the dorsal cavity and the ventral cavity 17. What two subcavities are found in the dorsal cavity? 18. What three subcavities are found in the ventral cavity? 19. What is the name of the structure that separates the thoracic cavity and the abdomin al cavity? 20. The vertebr al cavity is _________ (use the correct directional term) to the cranial cavity. 21. The thoracic cavity is _________ (use the correct directional term) to the abdomin al cavity. .