THE DURA MATER OF THE BRAIN. 7 



ing from the foramen spinosum it divides near the upper border 

 of the squamosa into two large branches, the anterior and posterior. 

 The posterior runs horizontally backward just below the squamo- 

 parietal suture and then ascends over the posterior half of the 

 parietal bone. The anterior branch runs upward a half-inch 

 behind the coronal suture. -It may be located, according to 

 Quain, at one inch, at one inch and a half, and at two inches 



Fig. 5. Median section of skull showing middle meningeal artery. 

 (After Morris's Anatomy.) 



behind the zygomatic process of the frontal bone and above the 

 zygomatic process of the temporal bone. 



The following nerves give branches to the dura: Troch- 

 lear, ophthalmic, semilunar ganglion, vagus and hypoglossal 

 of the cerebral group; and the sympathetic. The motor fibers 

 supply the meningeal arteries. 



Six Points of Difference in the Dura of the Cord. Absence of 

 processes, of sinuses, of arachnoid granulations, and of periosteal 



