THE BRAIN 



nucleus by the internal capsule (Fig. 216). It is now tri- 

 angular or wedge-shaped. Its base is turned towards the 

 external capsule, the claustrum, and the insula ; its medial 

 surface is applied to the internal capsule ; whilst its inferior 

 surface is directed downwards towards the base of the brain. 

 But, further, two white laminae are now evident, the external 



Longitudinal fissure 



Chorioid plexus 

 Lateral ventricle 



Claustrum 



Corpus callosum 

 /Fornix 



Tela chorioidea of 

 Xthird ventricle 



^Caudate nucleus 

 --Vena terminalis 



--Thalamus 

 --Ventricle in. 



Chorioid plexus 

 --Internal capsule 



-For. interventriculare 

 Column of 

 fornix 

 -Optic tract 



"Anterior commissure 

 Optic nerve 



Puta 



Globus pallidi 



Amygdaloid nucleus 

 Fasciculus thalamo-mamillaris 



Substantia perforata anterior 



| Olfactory tract 

 I ; Optic chiasma 



Infundibulum 

 Column of fornix 



FIG. 2 1 6. Frontal section through the Cerebral Hemisphere in such a plane 

 as to cut the three parts of the lentiform nucleus ; the posterior cut 

 surface of the anterior part of the hemisphere is depicted. 



and internal medullary lamina, which traverse its sub- 

 stance and divide it into three zones. The lateral, basal, 

 and larger zone is termed the putamen (Fig. 2 1 6). It is 

 darker in colour than the other two zones, and is traversed by 

 fine radiating white streaks. The two medial zones are of a 

 faint yellowish tint, and together they form what is termed 

 the globus pallidus (Figs. 213 and 216). The putamen has a 

 greater antero-posterior length than the globus pallidus. It 

 follows from this that it alone is connected with the head of 



