BASAL GANGLIA 



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out penetrated by white matter, which subdivides its contained gray cells 

 ' : nto four more or less distinct masses termed nuclei, viz.: an anterior, a 

 lateral, occupying the external part of the thalamus, a ventral, close to the 

 entire ventral surface, and a posterior, situated beneath the pulvinar. Be 



FIG 241. HORIZONTAL SECTION THROUGH THE CEREBRUM SHOWING THE NATURAL RELATIONS 



OF THE VARIOUS STRUCTURES. 



'neath and somewhat internal to each optic thalamus there is a region, the 

 subthalamic, 'consisting of an intricate network of nerve-fibers and several 

 nuclei of gray matter, e.g., the red or tegmental nucleus, the subthalamic 

 nucleus, or Luys' body, and the substantia nigra. f 



Though the thalamus has extensive connections with many po 



