SIMIA SAT^RIS, THE ORANG-OUTANG 



495 



\()\iv IS i\lati\c'l\' rich. The pr()ti>t\ ])r ofcacli lissurc IduiuI in tht- human brain 

 is iJicsiiit ill orano;. This gixt's the liDiUal lohc a ch'stinctl\ hunianoid appear- 

 ance. The proportion between the frontal and jxirieto-occipito-temporal 



^tRsacv^ 



FIG. 22j\\. DErAILED DIA(;K\M OF LEFT LATERAL SURFACE OF BRAIN, 



OKANOOL TA.NG. 



Key to Diagram, ramus post., Ramus Posterior of Sulcus Temporalis Superior; sli.c. fr. oi>.. Sulcus 

 Fronto-opcrcularis; s. VR. or., Sulcus Fronto-orbitalis; sllc. occip.. Sulcus Occipitalis; sulc. occip. lat.. 

 Sulcus Occipitalis Lateralis; sui.c. precnt. inf.. Sulcus Precentralis Inferior; sulc. prec.nt. sup.. Sulcus 

 Precentralis Superior; sulc. r. int.. Sulcus Retrocentralis Inferior; sulc. ret. sup.. Sulcus Retrocentralis 

 Superior; sulc. temp, med.. Sulcus Temporalis Medius; si i.e. ti-mp. sup.. Sulcus Temporalis Superior. 



areas appears to he about the same as in man. Actual planlmetric measure- 

 ments, h()\vc\er, show a dis|)arlty in this regard w hich hixors tlie trontal area 

 of the human brain. The com nhitions ol the occipital lobe are lairly rich, but 

 less marked than in an\ othtr region. Upon the mesial surface a deep annec- 

 tent gyre comes to the surface and thus inti'rrupts the direct continuity of the 

 sulcus simiarum with the occipital sulcus. This interruption by means of an 

 annectent ^'\'re in the course' of this lissure is a teature lrec|uently found in 

 the brain of the yreat anthropoids. 



