268 PRACTICAL HISTOLOGY [XXXIII 



In the lateral region, about half-way from dorsal 

 to ventral surface, the largish stained mass of the in- 

 ternal corpus gen. 



Laterally of the i. c. g., a band of oblique fibres, 

 fibres of the optic tract', bundles of fibres issue from the 

 medio-ventral side of the i. c. g. forming its brachium. 



Dorsally of the i. c. g. and optic tract, the external 

 corpus geniculatum ; fibres from the optic tract run into 

 and over it. 



The corpus mammillare on each side of the mid-ventral line ; 

 according to the position of the section, the anterior pillar of the 

 fornix may be seen on its dorso-lateral side, and the mammillo- 

 thalamus bundle on its dorso-rnedial side. 



A small part of the a. c. q. is seen ; in it laterally are bundles of 

 fibres its anterior brachium ; in the middle line over the aqueduct 

 are a number of transverse fibres (deep white and posterior cerebral 

 commissure fibres). Meynert's bundle will be seen laterally of the 

 lower part of the ventral grey substance. 



13. Section through the anterior part of the anterior corpus 

 quadrigeminum and geniculate bodies (man). Note : 



The red nucleus, consisting of large nerve cells in the region of 

 the crossed s. c. ped. ; fibres of the 3rd nerve run through its medial 

 part. 



The deep white substance of the a. c. q. spreading out laterally 

 into the tegmentum ; some fibres of the fillet (anterior mid-brain 

 fillet) may be seen running dorsally of the deep white, but they are 

 not very distinct. 



The pulvinar of the optic thalamus, laterally of the a. c. q. 



Between the pulvinar of the optic thalamus and the pes an oval 

 grey mass, the internal corpus geniculatum. 



Fibres of the optic tract attached to the lateral surface of the pes, 

 and running over and into a roundish body, the external geniculate 



