258 



PRACTICAL ANATOMY. 



inferior longitudinal along the median line of the upper 

 surface of the tentorium cerebelli; it empties into the 

 superior longitudinal. 



Lateral. Formed by the division of the superior 

 longitudinal. Pass horizontally outward on the horizontal 

 grooves of the occipital cross, then curve down behind 





FIG. 111. DIAGRAM SHOWING THE CEREBRAL SINUSES IN PROFILE. 



1. superior longitudinal sinus ; 2. inferior longitudinal sinus : 3. straight sinus, deriv- 

 ing blood from 1 and also from the veins of Galen (II) ; Nos. 1. 2, and 3 hound the falx 

 cerebri : 4, the torcular Merophili. where four sinuses meet: 5. lateral sinus: fi, superior 

 petrosal sinus, joining the lateral sinus (5) with the cavernous sinus (8) : 7, inferior petro- 

 sal sinus, joining the cavei'nous sinus (,S) with the jugular vein (9) : H, cavernous sinus; 

 9, internal jugular vein formed by two sinuses (5 and?); It), occipital sinus ; 11, venae 

 Galeni ; 12, vein passing to nas.il cavity ; 13, foramen caecum. 



the petrous bone, and terminate at the posterior lacerated 

 foramina. 



Occipital. Two small sinuses from the sides of the 

 foramen magnum; they empty into the lateral sinuses 

 near the point of their communication with the superior 

 longitudinal. 



Cavernous. Consists of a series of cells opening into 

 one another; lies in the cavernous groove at the side of 

 the body of the sphenoid. It drains the orbit, receiving 

 the ophthalmic vein. 





