376 . SPECIAL ANATOMY. 



forwards tQforam.jugulare, and passes into thebulbusven.jugu- 

 laris. They are connected by means of an emissarium Sant. in 

 the foram. mastoid. with Vv. occipital, superficiales, and receive, 

 besides the veins of the posterior cerebral lobes, cerebellum and in- 

 ternal ear, the sinus petrosus superior, and partly the occipitalis 

 posterior. 



5. Sinus petrosus superior, passes along the superior angle of 

 the petrous bone in the tentorium, connected at the apex with sin. 

 cavern., and opens behind and externally in sin. transvers. 



6. Sinus occipitalis posterior, descends singly or double from 

 the inferior circumference of the torcular, in the falx cerebelli to 

 the posterior border offoram. magnum, opening right and left into 

 the sin. transvers., and into plexus venos. spinalis. 



Torcular Herophili s. confluens sinuum, is the expanded point 

 before the protuberantia occipitalis interna, where the above- 

 mentioned sinus meet together with five (or six) orifices. 



Sinus which meet together in the confluens sinuum anterior^ 

 between the apex of the petrous bone and the sphenoid of either 

 side: 



7. Sinus petrosus inferior, passes in the groove between the 

 internal inferior border of os petros. and the pars basilar. oss. oc- 

 cipitis, between for am. lacerum posticum and anticum, connected 

 in front with sin. cav&rnos. and occipital, anter., opening under 

 sin. transvers. at the anterior circumference in the V. cephalica 

 interna. It unites the anterior and posterior sinus of the basis 

 cranii. 



8. Sinus occipitalis anterior (transversus) s. basilaris, a trans- 

 verse venous plexus lying upon the clivus, uniting the sin. petros. 

 infer., as also the sinus cavernosi of the right and left side with 

 each other, 



9. Sinus cavernosus, situated at the sides of the sella Turcica, 

 between the apex of the petrous bone and thefissura sphenoidalis, 

 is wide and cellular by means of numerous fibrous bands, is per- 

 forated by carotis interna, plexus caroticus and N. abducens, and 

 has on the external wall the JV. oculo-motorius. 



At the anterior external extremity (sinus ophthalmicus) it re- 

 ceives the Vv. ophthalmicee,V.fossce Sylvii connected with that of 

 the other side below the hypophysis by means of sinus circularis 

 inferior, by means offoram. lacerum anterius with plexus ptery- 

 goid., and opens behind into the sinus petrosi. Into it open : 



10. Sinus circularis Ridleyi, which surrounds the pituitary 

 gland in the sella turcica. 



11. Sinus spheno-parietalis s. alee parvce, lies on the lateral 



