134 



THE CORPUS STRIATUM. 



transverse vertical section through the middle (figs. 97 and 98), this nucleus appears 

 triangular, having a lateral, a mesial and an inferior surface, facing respectively the 

 external capsule, the internal capsule, and the base of the brain. Two white lines 

 (medullary lamina), parallel to the lateral border, divide it into three zones, of 

 -which the outer (putamen, Burdach, figs. 97, 98, pu.} is the largest and of a dark 



Fig. 98. VIEW FROM BEHIND OF A FRONTAL SECTION THROUGH THE RIGHT HEMISPHERE TAKEN JUST 

 BEHIND THE OPTIC CHiASMA. (E. A. S. ) From a photograph. 



c.c. , corpus callosum ; /o., body of fornix : ///., third ventricle ; v.l., lateral ventricle ; n.c., nuclei!.; 

 caudatus ; str.m., stria medullaris ; ih., thalamus ; c.i., internal capsule ; ffl.p., globus pallidus ; pu., 

 putamen ; c.e., external capsule ; cl., claustrum ; i.R., insula ; n.ainyy., nucleus amygdalae ; A, anterior 

 end of hippocampus major projecting into the descending cornu of the lateral ventricle ; tr. , optic tract ; 

 ch., optic chiasma ; n.opt., optic nerve ; c-m.s., callosotnarginal sulcus; Ro.s., Rolandic sulcus ; in-p.s., 

 intraparietal sulcus ; Sy., Sylvian fissure ; pll.s., parallel fissure ; inf.t.s., second temporal sulcus ; 

 coll. s. , collateral sulcus. 



reddish colour marked with fine radiating white striae, whilst the inner two, known 

 conjointly as the globus pallidus (gl.p.}, are yellowish in tint. On its outer side is a 

 grey lamina, termed the claustrum (cl.*), which is separated from the lenticular nucleus 

 by the stratum of white substance named the external capsule (c.e.). The internal 

 capsule (continuation of the crusta) separates it in the greater part of its extent 

 from the caudate nucleus and thalamus, but anteriorly the two nuclei of the corpus 

 striatum are united at their bases. Where it is widest (fig. 97) the lenticular 



