THE VEINS OF THE NECK. 



259 



Pituitary, or Circular. Encircles the sella turcica. 

 It connects the cavernous sinuses. 



Transverse. Connects the two great petrosal sinuses. 

 It is placed at the articulation of the os planum of the 

 sphenoid with the basilar process of the occipital. 



".......*" 



FIG. 112. DIAGRAM SHOWING THE VENOUS SINUSES OF THE DURA MATER. 



A, anterior fossa of skull : B, middle fossa: C. posterior fossa ; FS, frontal sinus: 1, 

 torcnlar Herophili ; 2, 2, lateral sinuses ; 3, 3, occipital sinuses : 4, 4, superior petrosal sinuses ; 

 5, 5, inferior petrosal sinuses : 6, transverse sinus : 7, 7, cavernous sinuses : 8, circular sinus , 

 9. opening into internal jugular vein ; 10, ophthalmic vein, communicating with cavernous 

 sinus (7) ; 11. a branch joining the occipital and inferior petrosal sinuses ; 12, veins from 

 posterior condyloid foramen to lateral sinus. 



Great Petrosal Is the continuation backward of 

 the cavernous sinus. It lies in the suture between 

 the petrous part of temporal and the side of the basilar 

 process. 



Lesser Petrosal. Lies in the superior border of the 

 petrous part of temporal and connects the lateral and the 

 cavernous sinuses. 



