THE BRAIN 



709 



caudate and lenticular nuclei. The thalamus is the representative 

 of the thalamencephalon of the primitive brain; the caudate and 

 lenticular nuclei, of the old brain, or archipallium. Alternating with 

 these nuclei of grey matter are strands of white matter; hence the 

 name of corpus striatum given to the whole. The relationship of these 

 structures is seen in Fig. 433. 



Of importance are the fibres which constitute the internal cap'sule 

 the tract of white fibres running anteriorly between the caudate and 



Caudate 



LentLcultxrNucie-j-S' 

 Clcutstrwtv 



es- 



Visual/ Fibres aT 

 OptLcSaudiaUon,. 



FIG. 433. HORIZONTAL SECTION THROUGH RIGHT CEREBRAL HEMISPHERE, SHOWING 

 POSITION OF THE VARIOUS STRANDS IN THE INTERNAL CAPSULE. (Purves Stewart, 

 after Beevor and Horsloy.) 



lenticular nuclei, and posteriorly between the thalamus and the 

 lenticular nucleus. Through this capsule sweep the fibres to and 

 from the various regions of the cerebral cortex. In the front 

 part of the anterior limb run fibres connecting the frontal cortex 

 with the pons and cerebellum (the front o-pontine fibres), and fibres 

 from the thalamus to the frontal cortex (the thalamo-f rental fibres). 

 In the neighbourhood of the knee, or genu, of the capsule, run efferent 

 motor fibres from the cortex. In the posterior part of the anterior 



