6o2 THE HIGHER ANTHROPOIDS 



More iiii])()rl;ml than the cnuTgeiit hbcrs ol the oeuloinotor nerve are 

 the commissural and deeussatm<2; axons w hieh connect the nLiclei of the two 

 sides. The e.\tensi\ cness ol this mternuclear connection in t'hiinpanzee is 



FIG. 268. CHIMPANZEE. LEVEL OF THE SUPERIOR COLLICULUS. 

 CEN', Central Gray Matter; cp, Cerebral Peduncle; ctf. Central Tegmental Tract; mf, Mesial Fillet; mcb. 

 Mesial Geniculate Body; NOC, Oculomotor Nucleus; nru, Nucleus Ruber; N'3, Oculomotor Nerve; pd, 

 Predorsal Bundle; pi., Posterior Longitudinal Fasciculus; rf.f, Reticular Formation; rst, Rubrospinal Tract; 

 SBN, Substantia Nigra; sc, Superior ('ollicuhis; spt, Spinotlialaniic Tract. [Accession No. 157. Section 530. 

 Actual Size 26 X 13 nun.) 



notable, since this intercommunication is related to hinoeular and stereo- 

 scopic vision. This animal possesses a iairlx hi^h degree of such vision. The 

 tests made by most caretul psyclioiogical nuestigalions, particularly in the 



