618 



THE VELXS 



the diploe terminate partly in the siipertieial veins already described, partly in the 

 venous sinuses of the eranium, and partly in the deep veins of the neck. The 

 vinous sinuses open into the deep veins of the neck. The veins of the brain ter- 

 minate in the venous sinuses. The veins of the nasal cavities terminate partly in 

 the deep, and to some extent m the superficial veins. The veins of the ear ynn both 

 the superficial and deep veins and the venous sinuses. The veins of the orbit ter- 

 minate partly in the superficial veins, but chiefly in the venous sinuses. The veins 

 of the pharynx and larynx enter the deep veins of the neck. 



1. THE VEINS OF THE DIPLOE 



The veins of the diploe are contained in bony channels in the cancellous tissue 

 between the external and internal tables of the skull. They are of comparatively 

 large size, Avith very thin and imperfect Avails, and form irregular communicating 

 channels. They have no valves. They can only be seen on removing the external 



Fig. 386. — The Veins of the Diploe. 

 (From a specimen iu St. Bartholomew's Hospital Museum.) 



THE LAMBOOID 

 SUTURE 



The occipital or 

 pa r ieto-oecip Hal 

 diploic vein 



The external pari- 

 etal or posterior 

 temporal diploic 

 ■vein 



THE MASTOID 

 FORAMEN 



THE CORONAL SUTURE 



The frontal di- 

 ploic vein 



The frontosphe- 

 noidal diploic 

 vein 



The /ronio-pari- 

 elal or anterior 

 temporal diploic 

 vein 



table of the skull with a file or chisel. They terminate in four or five main and 

 descending channels, Avhich open, some outwards through the external table of the 

 skull into some of the superficial and deep veins of the head and face, and some 

 inwards through the internal table into the venous sinuses. They- are divided into 

 the frontal. fronto-s])henoidal. fronto-parietal or anterior tem])oral, external i)arietal 

 or posterior temporal, and occipital or parieto-occipital. 



The frontal are contained in the anterior part of the frontal bone. They con- 

 verge anteriorly to a single vein which passes downwards, ])erforates the external 

 table through a small aperture in the roof of the supraorbital notch, and terminates 

 in the supraorV)ital vein. 



The fronto-sphenoidal are contained in the lateral parts of the frontal bone, 

 and. running' into the s]ihenoid Ixnie, terminate in the sinus ahe parva\ 



Tlic fronto-parietal, or anterior temporal, are contained in the posterior part 

 of the frontal and in the anterior part of the parietal bone. They pass downwards, 

 and end, ])artly in the deep tem](oral veins by perforating the greater wing of the 

 sphenoid bone, and ])avtly in the superior ]ietvosal sinus. 



The external parietal, or posterior temporal, ramifies in the parietal bone. 



