Arteries of the Head. 



403 



A. communieans anterior 



A. cerebri anterior 



A. chorioid 



\ . ophthalniica 

 A. earotis interna 



communieans 

 posterior 



A. cerebri media 



Ramus ad pontem 



A. basilaris 

 A. cerebelli inferior ' 

 posterior 

 A. spinalis anterior 



^ A. cerebri 

 posterior 



A. cerebelli 

 superior 



auditiva interna 



cerebelli inferior 

 anterior^ 



nalis posterior ' 



Tentorium cerebellij 



A. Tertebralis 



448. Arteries of the base of the brain in their 



relation to the skull after removal of the brain; viewed from above. 



(On the right side the a. earotis interna has been exposed in its course in the sinus cavernosus.) 

 1. A. yertebralis (continued) (see also Figs. 444 446): 



c) A. spinalis posterior, delicate, bends around the lateral margin of the medulla oblongata 



and runs downward, forming anastomoses with that of the other side, in the sulcus 

 lateralis posterior of the spinal cord, in fi-ont of and lateralward from the posterior 

 roots; it imites with branches of the rami spinales of the a. vertebralis, aa. inter- 

 costales, lumbales and sacrales laterales and supplies the spinal cord and its membranes. 



d) A. spinalis anterior, delicate, unites with the artery of the opposite side at the upper 



end of the spinal cord and runs downward, impaired, in front of the fissura mediana 

 anterior as far as the filum terminale ; like the preceding artery it receives a variable 

 number of branches of the rami spinales, and supplies the spinal cord and its membranes. 



e) A. cerebelli inferior posterior (posterior inferior cerebellar artery) turns backward to 



the posterior part of the inferior surface of the cerebellum : it gives off branches to 

 the plexus chorioideus ventriculi quarti. 



