I 3 6 



PR A CTICAL ANA TOMY. 



The ganglionic or terminal end arteries will be seen in very great numbers 

 on lifting the middle, posterior, and anterior cerebral arteries. The}' are very 

 minute. Look closely, and you will see them passing through minute perfora- 

 tions to the interior of the brain through the perforated spaces. (Fig. 92.) 



The interpeduncular space has (i) boundaries; (2) contents. The con- 

 tents form the floor of the third ventricle. The boundaries are important 

 structures on the base of the brain which I wish you to study carefully. 



(iMo-. 93.) 



The Boundaries of the Interpcduiicniar Space. ( i ) Antero-laterally, optic 

 chiasm and optic tracts ; (2) postero-latcrally^ pons Varolii and crura cerebri. 



Contents of Interpeduncular Space. (i) The tuber cinereum ; (2) infundibulum, 

 pituitary body ; (3) the corpora albicantia, part of the fornix ; (4) posterior 



Anterior cerebral 

 artery 



Middle cerebral 



artery 

 Internal carotid 



i ir ten/ 

 Poster o-median 



perforating 

 Posterior cerebral 



artery 



Superior cerebellar 

 artery 



Anterior inferior 

 cerebellar artery 



Vertebral artery 



Posterior inferior 

 cerebellar artery 



Anterior com- 

 mvnicating 



artery 

 Antero-laternl 



perforiitin ff 

 Anterior choroid 

 Posterior 



conimnnicating 



artery 

 Posterior choroid 



Basilar artery 

 Cms cerebelli, cut 



Anterior spinal 

 artery 



FIG. 91. THE ARTERIES OF THE BRAIN. 

 (From a preparation in the Museum of St. Bartholomew's Hospital.) 



perforate space, for terminal end arteries ; (5) the third cranial nerve, motor 

 oculi nerve. 



Notice in particular : 



1. The optic tracts crossing the crura cerebri. 



2. The third nerve, motor oculi, between the crura cerebri. 



3. The terminal end arteries from the circle of Willis. (Fig. 91.) 



4. The basilar artery on the body of the pons Varolii. (Fig. 91.) 



5. The fourth nerve, coming out between the pons and crus cerebri. 



6. The fifth nerve, coming from the side of the pons Varolii. 



7. The sixth nerve, coming through between the pons and medulla. 



8. The seventh and eighth nerves, between the olivary and restiform bodies. 



9. The ninth, tenth, and eleventh nerves, between the olivary and restiform 

 bodies. 



10. The twelfth nerve, between the pyramid and olive. 



