298 



THE INTERMEDIATE PRIMATES 



poidea in general. The orbital surface of the frontal, the sphenoidal surface 

 of the temporal and the occipital surface of the occipital lobe all have 

 indications of the typical iissures found in these regions. Several deep 



FIG. 140. RIGHT L\TLKAL SURFACE OF BRAIN, PAPIO CYNOCEPHALUS. 



lActiKiI Length 89 mm.] 



Key to Diagram. r.\mus post., Ramus Porterior of Sulci Temporali Superior; SULC. front, orb.. 

 Sulcus Frontalis Orbitalis; sulc. occip.. Sulcus Occipitalis (Inferior); sulc. retrocnt. inf.. Sulcus 

 Retrocentralis Inferior. 



annectent gyres may be brought to light by the separation of the Sylvian 

 fissure as well as the presence of a faintly outlined series of radiating gyres 

 constituting the island of Reil. One deep annectent gyre is found midway 

 between the two extremities of the sulcus semilunaris. 



THE CEREBELLUM 



The cerebellum in Papio is characterized by the relatively large size 

 of the vermis which as yet manifests little tendency to lose its surface 

 prominence. The tentorial surface is sharply gabled, the vermis rising as a 

 marked median ridge-pole. The interfolial sulci are directly continuous with- 

 out fissural intciTLiption from vermis to lateral lobe. On the occipital surface 

 two paramedian sulci separate the vermis from the lateral lobes, although the 

 former have a marked prominence on this surface. The petroso-ventricular 

 surface presents three elements: (i) a high elevated portion of the superior 

 vermis, (2) the ventricular portion, and (3) the petrosal area. 



