228 



THE LOWER PRIMATES 



rectus muscles. This nerve also supplies all of the intrinsic ocular muscles 

 and the levator muscle of the upper eyelid. It is especially signiiicant that the 

 commissural connections of the nucleus oculomotorius are much more prom- 



FIG. 126. MYCETES ^il.\ UA LL S. LEVEL OF THE SUPERIOR COLLICULUS. 



CEN, Central Gray Matter; ctt, Central Tegmental Tract; cp. Cerebral Peduncle; mgb. Mesial Geniculate 

 Body; MF, Mesial Fillet; noc. Oculomotor Nucleus; nru, Nucleus Ruber; N3, Oculomotor Nerve; pd, 

 Predorsal Bundle; ref, Reticular Formation; rst, Rubrospinal Tract; sc, Superior Colliculus; sbn, Sub- 

 stantia Nigra; spt, Spinothalamic Tract. [Accession No. 148. Section 401. Actual Size 18X9 mm.] 



inent than m lemur or marmoset, thus implying a closer association in 

 interocular movements of the eyes and thereby securing a nearer approach 

 to binocular vision and stereoscopic fusion. 



Ventrolateral to the nucleus oculomotorius is the red nucleus (NRu) 

 which is iairly well dellned. It constitutes a rehiy station in the course of the 

 cerebello-spinal pathway. From it arise the fibers of the rubrospinal tract 

 (Rst) over which pass impulses necessary to muscular coordination. In 



