BLOOD SINUSES OF THE CEANIUM. 



973 



Sinus Sagittalis Superior. The superior sagittal sinus commences in the 

 anterior fOssa of the cranium, at the crista galli, where it communicates, through 

 the foramen csecum, with the veins of the nasal cavity or with the angular vein. 

 It passes backwards in the convex margin of the falx cerebri, grooving the 

 frontal, both the parietal bones, and upper part of the occipital. As it descends 

 along the occipital bone it usually passes slightly to the right side, and it ends. 



Sinus frontalis 

 Cellula ethmoidale anterior 



A. frontalis 

 A. supraorbitalis X N ^\ 



/^< 



Scalp 



Ossa frontale 



V. ophthalmica superior t 

 Aa. ethmoidales 



A. lacrimal 



A. oplithalmica " 

 leningea anterior- 



>s Ossa frontale (pars orbitalis) 



Sinus sphenoparietalis 



M. temporalis 



N. frontalis- 



X. trochlearis " 



caroti.s uiterna 



~ N. opticus 



\ Sinus intercavernosi 

 "."anterior 



JL-- Sinus cavernosus 

 , oculomotorius 

 Plexus basilari.s 



facialis et , 

 acusticus 

 petrosus 

 superior 



NM. glossopharyngeus 

 vagus et accessorius 



.Sinus occipitalis 



/ 

 Sinus transversus 



Sinus rectus 



A. vertebralis 



FIG. 788. THE LOWER BLOOD SINUSES OF THE DURA MATER. 



the specimen represented the superior sagittal sinus opened into both transverse sinuses and chietty into 

 the left. The straight sinus also opened into both transverse sinuses. The medial part of the ] 

 transverse sinus was divided by a horizontal septum into upper and lower parts, 

 figure passes below the septum. 



at the level of the internal occipital protuberance, by becoming the right transverse 

 sinus. Instead of passing to the right, it occasionally turns to the left, and ends in 

 the left transverse sinus, and in some cases it bifurcates and ends in both .transverse 

 sinuses. When it ends wholly in the right or the left transverse sinus its termina- 

 tion is associated with a well-marked dilatation, the confluens sinuum, which is 

 lodged in a depression at one side of the internal occipital protuberance, 

 confluens sinuum is connected, across the protuberance, by an anastomosing channel, 

 with a similar dilatation which marks the junction of the straight sinus with the 



