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A MANUAL OF ANATOMY 



nucleus caudatus is composed of grey matter, and its cells are of 

 the multipolar variety. 



The nucleus lenticularis is embedded in the white matter of the 

 cerebral hemisphere, and lies on the outer side of the nucleus 

 caudatus and optic thalamus, from both of which it is separated 

 by the internal capsule. It is of more limited extent than the 

 nucleus caudatus, and receives its name from the fact that, in 

 horizontal section, it presents the appearance of a biconvex lens, 

 the broadest part being on a level with the front of the optic 

 thalamus. Anteriorly it is closely related to the front part of the 

 nucleus caudatus, being continuous with it inferiorly, and con- 

 nected with it superiorly by striae of grey matter which intersect 

 the white matter of the front part of the internal capsule. The 

 anterior part of the nucleus lenticularis, as seen in coronal section, 



Great Longitudinal Fissure 



Fifth Ventricle (within 

 Septum Lucidum) 



Anterior Cornu of 

 Lateral Ventricle 



Left Anterior . 

 Pillar of 

 Fornix 



Middle Com-', 

 missure 



Third Ventricle -S§^-" 



Genu of Corpus Callosum 



Caudate Nucleus 



.Optic Thalamus 



Internal Capsule 



^^ , External Caps 

 Claustrum 



-Grey Matter ( 

 Island of Rei 



^ White Matter o 

 Island of Reil 



Optic Tract (cut) 



Infundibulum 



Lenticular Nucleus 



Fig. 596. — Coronal Section of the Frontal Portions of the Cere- 

 bral Hemispheres, passing through the Anterior Cornua of thb 

 Lateral Ventricles (Posterior View). 



1, Putamen of Lenticular Nucleus ; 2, 3, Globus Pallidus of Lenticular 



Nucleus. 



is somewhat semilunar. When such a section is made through the* 

 centre, the nucleus presents a triangular outline, the base being 

 directed towards the island of Reil, and having the external capsule, 

 in loose connection with it, whilst the internal surface is in contact 

 with the internal capsule. In such a section the nucleus is seen 

 to be traversed vertically by two white bands, called the medullary 

 lamina, which divide it into three zones. The outer zone, which 

 has a dark reddish colour, is the largest, and is called the putamsn. 



