194 THE BRAIN. 



It may be convenient here to recapitulate the sources of the blood supply to the 

 several parts of the encephalon. 



The medulla oblongata and pons Varolii are supplied by branches from the 



Fig. 136. THE ARTERIES OF THE BASE OF THE CEREBRUM. (G. D. T., after Duret, and from nature.) 



On the left side of the brain the temporal lobe is cut away so as to open the inferior and posterior 

 horns of the lateral ventricle. The mid-brain is divided close above the pons and the posterior cerebral 

 arteries are cut at their origin from the basilar. 



Central arteries (to the basal ganglia) : am, antero-mesial group arising from the anterior cerebral ; 

 al, antero- lateral group, from the middle cerebral ; pm, pi (on the optic thalamus), postero-mesial and 

 postero-lateral groups, from the posterior cerebral. 



Choroidal arteries: a ch, anterior, from the internal carotid ; p ch (on the splenium), posterior, from 

 the posterior cerebral. 



Peripheral arteries: 1, 1, inferior internal frontal, from the anterior cerebral ; 2, inferior external 

 frontal ; 3, ascending frontal ; 4, ascending parietal, and 5, temporo-parietal, from the middle cerebral ; 

 6, anterior temporal, 7, posterior temporal, and 8, occipital, from the posterior cerebral. 



anterior spinal, the vertebral, the basilar, and the posterior cerebral arteries. The 

 branches enter the pons and medulla oblongata in two sets, lateral or radicular 



