Veins of the Head. 



443 



Vv. meningeae f 

 Siuus sagittalis superior ^ 



,'Vv. menirgeae mediae 



Sinus sagittalis inferior^ 



Falx cerebri 



V. etbmoidalis 

 posterior 



V. cerebri magna 

 [GaleniJ 



I Sinus rectus 



V. 



etbmoidalis 

 anterior 



'/V 



h 





bmus 

 trans versus 



Brauclies 



of tbe V. spheno 



palatina 



Plexus 

 basilaris Sinus' 



petrosus inferior 



Sinus 

 occipitalis 



Plexus venosi 

 vcrtebrales interni 



484. Sinus durae mat r is of the right half of the skull, 



viewed from the left. 



b) V. ophthahnica inferior (see Fig. 488), devoid of valves, arises from the veins of the 



tear-sac, of the eyehds, &c., in the anterior part of the orbit, between the medial and 

 inferior wall : it runs in the inferior part of the orbit and divides into two branches. 

 One branch goes backward through the fissura orbitahs superior into the sinus caver- 

 nosus ; the other passes lateralward through the fissura orbitalis inferior and opens into 

 the ramus profimdus of the v. facialis anterior. It receives vv. musculares and veins 

 of the bulbus oculi and anastomoses medianward with the v. ophthahnica superior. 



c) Sinus sphmoparictalis (see Fig. 483), paired, begins on each side a little behind the 



sutura coronalis on the parietal bone in a bonv groove or in a bony canal, turns 



medianward beneath the ala parva ossis sphenoidalis and enters the anterior end of the 



sinus cavemosus. It receives usually one v. meningea media, vv. cerebri inferiores 



(from the fissura cerebri lateralis [Sylvii]), as weU as the v. ophthalmomeniufjea, and 



often, also, the v. dijdoica temporalis anterior. 



7. and 8. Siuus iutercavernosus anterior and siuus intereaveruosus posterior 



(see Fig. 483), unpaired, run in front of, behind and partly also beneath thi| hypophysis and 



unite the two sinus transversi Avith each other. They form, with these, the siuus circularis. 



9. Siuus petrosus superior (superior petrosal sinus) (see Fig. 483), paired ,^ goes 



lateralward and backward on each side, from the posterior part of the sinus cavernosus in the 



sulcus petrosus superior of the temporal bone and in the attached margin of the tentorium 



cerebeUi, to the sulcus sigmoideus and into the sinus transversus. 



