

TEXT-BOOK OF PHYSIOLOGY 



netrated by white matter, which subdivides its contained gray cells 

 "to four more or less distinct masses termed nuclei, viz : an anterior & 

 a ^/occupying the external part of the thalamus, a ventral, close to ti 

 eofre ventral surface, and a posterior, situated beneath the pulvmar. Be- 



Fio. 238. 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. 



Though the thalamus has extensive connections with many portions of 



