Spine, internal vertebral venous plexus, cranial sinuses, shown in situ, in 2 numbered illustrations. 1 illustration of skull, spine and pelvic bones divided in sagital section to show cranial sinuses and internal vertebral venous plexus. Ribs, epigastric arteries and veins, internal thoracic arteries and veins also shown. Medial view. 1 illustration of spine divided in coronal section, spinous process of the vertebrae removed to show internal vertebral venous plexus, posterior view.