MYCETES SENICULUS 229 



this sense the size of the nucleus nil)er furnishes some chie of the coor- 

 dinating capacity of the animal. Although more prominent than in marmoset 

 or lemur, the nucleus ruber is not so large as in some of the higher apes, which 



FIG. 127. MYCETES SENICULUS. LEVEL OF THE OPTIC CHIASM. 

 ciN, Internal Capsule; for. Fornix; fpd. Descending Pillar of Fornix; glb. Globus Pallidus; opx, Optic 



Chiasm; put, Putamen; th, Thalamus. [Accession No. 148. Section 501. Actual Size 28 X 17 mm.] 



seems to justify the supposition that the animal's eoordinative powers lie 

 somewhere intermediate between the lowest and highest differentiation in 

 the primate scries. 



LEVEL OF THE OPTIC CHIASM (FIG. 1 27) 



At this level the section shows the changes incident to the appearance 

 of the optic thalamus (Th) and the optic decussation (Opx). The massive 



