Chapter W 1 1 



SI MIA SATYRUS, THE ORANG-OUTANG, ITS BRAIN 



AND BEHAVIOR 



lis Pdsilion cimouii ihc Primates; .\[casurcmcnts and Bruin Indices; Surface 

 Markiniis aj llw Brain and Brain Stem; Structure o/ the Brain Stem in 



Cross Sec I ion 



IT tlu' orang-outang enjoys a reputation less romantie than cither of his 

 great congeners, the ehinipan/t't' and the gorilla, this is clue to his insular 

 habitat which has lelt hini sonu'uhat inaccessible to the attentions of 

 European curiosity. \\ hate\'er bibulous repute he nia\ have among the 

 natives ot his island home, he has had less opportunity to tall into the nimble 

 hands ot the modern table-makei's. It is particularly tortunate that the story 

 ot his life appears to have had its lirst real introduction to civilization through 

 the auspices of one of the most celebrated of naturalists, Alfred Russell 

 W allace. 



Appearance and Habiis of the Orang-Outang 



The orang is found onl\- in Borneo and Sumatra, and there seems to be 

 considerable doubt as to whether the animals found in these two localities 

 constitute distinct species. It is the custom for most systems of classifica- 

 tion to designate one as the Bornean orang and the other as the Sumatran 

 orang. The adult animal has a heav^- body, short thick neck, a round head 

 and somew hat receding forehead, a distinctly protruding muzzle with large 

 mouth, broad lijjs and face uncovered by hair. The lips arc mobile and 

 l)rotrusive. The arms are very long, reaching to the ankles in the upright 

 posture. The hands arc long and narrow and the thumb is short. The 

 lingers are united by webs at the base of the proximal phalanges. The legs 



479 



