Arteries of the Head. 



399 



A. cerebri anterior' 



A. communicans anterior 



Lobus frontalis 



A. cerebri media 



A. carotis- - 

 interna 



A. ciiorioidea 



A. coi^municans -- 



posterior 

 X. ociilomotorius " 



A. cerebelli - _ 

 superior 



A. cerebri- - 

 posterior 

 A. basilaris- - 



Lobus occipitalis' <*' " 



A. auditiva interna^ / 

 A. cerebelli inferior anterior 



A. vertebralis 

 A. spinalis anterior 



\ Ramus 

 \ ad pontem 



^N. abducens 



N. facialis 



^A. cerebelli inferior 

 \ posterior 



A. spinalis posterior 



Cerebellum 



444. Arteries of the base of the brain. 



(The pole of the right temporal lohe and the right side of the cerebellum have been cut away.) 

 2. A. ophthalmica (continued). 



h) J. eihmoidalis anterior (see Figs. 439, 440 and 443) passes through the foramen 

 ethmoidale anterius upon the lamina cribrosa, there gives off the a. meuingea anterior 

 upward to the dura mater, then ])prforates the lamina cribrosa and supplies the 

 anterior part of the wall of the nasal cavity. 



i) Aa. palpebrals mediales (not illustrated), one in each eyelid lateralward ; they form by 

 anastomosis of each medial artery with one a. palpebralis lateralis (from the a. lacri- 

 malis), the arcus tarseus superior and inferior, situated near the free margin of 

 the eyelid , in front of the tarsus. They give off fine branches to the conjunctiva 

 (aa. cortjunctivales posteriores). 



k) A. dorsalis nasi (0. T. nasal branch) (see Figs. 436 and 441) perforates them, orbi- 

 cularis oculi above the ligamentum palpebrale mediale, passes downward and anasto- 

 moses with the a. angularis (from the a. maxillaris externa). 



1) A. frontalis (see Figs. 436, 437, 441 and 443) goes through the incisura frontalis to 

 the forehead and supplies the muscles and skin in that situation. 



26* 



