132 



THE LOWER PRIMATES 



position constitute the decussation of Forel, many of whose axons appear 

 to take origin in the red nucleus (NRu), cross the midline and enter into 

 that descending bundle which constitutes the rubrospinal tract. On the 



FIG. 62. TARSIUS SPECTRUM. LEVEL OF THE ANTERIOR COMMISSURE. 



AC, Anterior Commissure; cin. Internal Capsule; cix, External Capsule; fdp, Descending Pillar of Fornix; 

 FOR, Fornix; len. Lenticular Nucleus; XCA, Nucleus Caudatus; nep. Neopallium; th, Tlialamus. [Accession 

 No. 210. Section 305. Actual Size 15 X 7 mm.) 



htteral periphery of the section and ventral to the superior colhcukis is 

 the mesial geniculate bodv (IVlgb). 



LE\EL OF THE OPTIC CHIASM (FIG. 61) 



At the level of the optic chiasm the bram stem is seen approaching its 

 caudal extremity. The third ventricle is here Hanked upon either side by 

 the massive thalamic groups of nuclei, and the roof formed by some fibers 



