CRANIAL CAVITY. 



compartment behind the preceding; the spinal portion of the 

 spinal accessory enters the cranium through the foramen mag- 

 num. The hypoglossal root bundles both pierce the dura 

 separately and unite in the anterior condyloid foramen or after 

 leaving the skull. [689-696] 



In the cavernous sinus the ophthalmic communicates with 

 the oculo-motor, trochlear, and abducent; all of them com- 

 municate with the sympathetic cavernous plexus. 



Meningeal Nerves. Superior maxillary : a recurrent branch 

 arises in the cranium. Inferior maxillary : recurrent branch 

 enters through the foramen spinosum. Ophthalmic : a recur- 

 rent branch arises in the cavernous sinus. Vagus : a meningeal 

 branch arises from the root ganglion. Hypoglossal: a recur- 

 rent branch. Cervical plexus : a meningeal branch ascends on 

 the hypoglossal. 



ARTERIES. 



Internal Maxillary. The middle meningeal enters by the 

 foramen spinosum, ascends in a groove on the great wing of 

 the sphenoid, and divides. Branches: petrosal, entering the 

 hiatus Fallopii; gasserian, to that ganglion; tympanic, entering 

 the petro-squamous suture or Tensor tympani canal; orbital, 

 entering the sphenoidal fissure; anterior terminal, ascending 

 past the antero-inferior angle of the parietal ; posterior termi- 

 nal, running backward over the squamous part of the tempo- 

 ral. The small meningeal enters by the foramen ovale. [810] 



Internal Carotid. This traverses the carotid canal to the 

 apex of the petrous bone, crosses the foramen lacerum medium, 

 runs in the outer wall of the cavernous sinus to the lower root 

 of the small wing of the sphenoid, ascends to the brain, and 

 divides into the anterior and middle cerebral. Branches in 

 canal: tympanic, piercing the posterior wall; Vidian, entering 

 the Vidian canal. Branches in cranium: cavernous, to that 

 sinus; gasserian, to the ganglion; pituitary, to the pituitary 

 body ; meningeal ; ophthalmic, running under the optic nerve 



[47] 



