NERVOUS SYSTEM. VERTEBRATA. 395 



D. 569. The brain of a Red Uakari (Brachyurus rubicumlus). 

 Both cerebral hemispheres have been detached. 



This brain clearly resembles that of PitJiecia satanas 

 (D. 566). 



The Sylvian fissure (superficially) joins the parallel sulcus 

 on both sides. 



The peculiar relation of intraparietal and parieto-occipital 

 sulci found in Pithecia also occurs here. 



The Simian sulcus is more rudimentary, whereas the 

 inferior occipital is deeper and its upper lip tends to become 

 opercular. 



The sulcus rectus is plain. The orbital sulcus is H- 

 shaped. 0.0. 1337 vb. 



D. 570. Cast of the cranial cavity of Brachyurus calvus. 



D. 571. The right cerebral hemisphere of a Red Howler (Alo- 

 natta senicula), (<J) (figs. 232 & 233). 



Fig. 232. (xf.) 



SULC. CENT. ? 

 SULC. INTRAPAR / SULC. RECT. 



SULC. ORB. 



SULC PAR 



Fig. 233. (Xf). 



bUl.l CALL.MAR6. 



SULC. PAR.OCC. 



This presents some resemblance to the brain of Nycti- 

 pithecus. 



