THE VEINS OF THE NECK. 257 



the external jugular. The facial generally empties into 

 the internal jugular. 



THE VEINS OF THE NECK. 



External Jugular. Begins in the substance of the 

 parotid gland, runs down the neck from the angle of 

 the inferior maxillary to the middle of the clavicle, and 

 empties into the subclavian. 



Posterior External Jugular. Empties into the exter- 

 nal jugular about its middle ; comes from posterior part 

 of the neck. 



Anterior Jugular. Formed by the submaxillary 

 veins, passes down the anterior part of the neck, and 

 empties into either the external jugular or subclavian. 



Internal Jugular. Begins at the posterior lacerated 

 foramen, and is the continuation of the great lateral sinus 

 of the brain. It runs deeply down the neck to the outer 

 side of the carotid, and empties into the subclavian to 

 make the innominate. 



Vertebral. Runs down the spine beside the vertebral 

 artery and empties into the innominate. 



The deep veins of the head are diploic sinuses, canals 

 in the diploic substance of the cranial bones. The veins 

 in these canals adhere to the walls and remain open on 

 section. The sinuses of the dura mater are a simple 

 separation of the layers of the dura mater, and are lined 

 by endothelium. They are : 



Superior Longitudinal. Begins at the foramen 

 caecum, in front of the cristi galli. It runs along the 

 median line of the skull to the internal occipital pro- 

 tuberance, where it divides into the two lateral ; the 

 point of division is called the torcular Herophili. 



Inferior Longitudinal. Along the free border of the 

 falx cerebri; terminates posteriorly in the straight sinus. 



Straight. Is the continuation backward of the 



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