A Study of Cerebral Anthropology 63 



The sulcus frontalis inferior is in the form of an inverted " T." 

 It is superficially confluent with the middle, frontal and inferior 

 praecentral sulci. Aside from a few superficial variations there 

 is a remarkable similarity of fissure arrangement of the right and 

 left frontal regions. 



The interparietal fissure complex is somewhat more simple than 

 the left. The retrocentral sulci are interrupted by annectants 

 above and below that assist us in interpreting the condition. The 

 inferior indicates that the confluence of the retrocentralis inferior 

 with the fissura Sylvii is through the sulcus subcentralis posterior, 

 while the upper annectant represents the point of division between 

 the sulci retrocentrales inferior and superior. A connection is 

 present between the sulcus retrocentralis inferior and the sulcus 

 interparietalis. But from its direction and depth it may be taken 

 as a superior branch of the latter sulcus or possibly as a continua- 

 tion of the anterior ramus of the ascending portion of the superior 

 temporal sulcus. In either way we can consider that the sulcus 

 interparietalis is separated from the other sulci of the group form- 

 ing, as on the left, an example of type V. The sulcus interparie- 

 talis is divided by an annectant into two segments, the posterior 

 being connected with the sulcus occipitalis transversus, which is 

 simple, as on the left. 



At the posterior occipital region the arrangement is very com- 

 plex, and it is difficult to identify the various fissures which are 

 undoubtedly present. The inferior occipital fissure is well devel- 

 oped, and the lunate fissure is present but not in typical form. 

 The remaining furrows I will not attempt to identify; for they 

 are not important being only from three to six millimeters deep. 



The sulcus temporalis superior is made up of two parts, the 

 ramus anterior and ramus ascendens which are entirely separated 

 (this interpretation is based on the condition present on the left 

 side), there are no branches cutting into the fissura Sylvii and 

 the gyrus temporalis superior is narrow and poorly developed. 



The sulcus temporalis medius is branched, as on the left, giving 

 to the middle temporal convolution a very broken surface. 



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