CHAP. XXL] 



OF THE HUMAN BRAIN. 



383 



" The external perpendicular fissures (fig. 135, P) can be 

 traced as easily as in the Hottentot Venus (fig. 134, F), but 

 are soon interrupted by the external connecting convolu- 

 tions (a, /3). Towards the sides these fissures are cer- 

 tainly more easily followed than in the European a cir- 



IF 



:ar 



FIG. 138. Vertex View of the Brain of a Scotchman. (After Turner.) 

 Fr, Frontal lobe; Par, parietal lobe; Oc, occipital lobe; S F, eupero-froutal, 

 IF, infero-f rental fissure ; R, fissure of Rolando ; /P,intra-parietal, and .P 0, parieto- 

 occipital fissure ; S, horizontal, and S', ascending limb of the Sylvian fissure ; 

 A, supra-marginal lobule. 1, 1, Inferior, 2, 2, middle, and 3, 3, 3, superior frontal 

 convolutions ; 4, 4, ascending frontal, and 5, 5, ascending parietal convolution ; 

 5', outer, and 5", inner part of postero-parietal lobule ; 6, 6, angular convolution ; 

 10, superior occipital convolution, a, a, first, and ft second annectent convolution. 



cumstance which imparts a lower character to this part of 

 the Bosjes brain ; at the same time they are far more 

 interrupted than in the Chimpanzee or Orang-outan. 

 These short external perpendicular fissures join as usual 

 the summits of the internal perpendicular fissures, and, 



