A Study of Cerebral Anthropology 6i 



and back divides about the middle of the lobe into two branches. 

 The shallower of the two continues in the direction established by 

 the fissure and terminates in the fissura Sylvii. The other branch, 

 which is the real continuation of the segment, turns backward 

 and continues in an uninterrupted course to the occipital pole. 

 At the point where the ramus ascendens is ordinarily given off, a 

 shallow furrow connects it with two ascending rami, which pass 

 up and back, one parallel to the retrocentral fissure to end in the 

 interparietal, the other somewhat more horizontally backward to 

 become confluent with the fissures of the occipital region. I have 

 frequently encountered this fissure pattern in negro brains. Schu- 

 ster has figured a similar condition for a Chinese brain. 



The sulcus temporalis medius is very tortuous and branched, 

 cutting the middle temporal gyrus up into many secondary folds, 

 but it does not form any connections except with the inferior oc- 

 cipital sulcus already referred to. 



Mesial and Inferior Surfaces 



The mesial surface gives the appearance of being very com- 

 plexly convoluted due to the many branches of the fissures. The 

 sulcus rostralis is deep and well developed, at its inferior extrem- 

 ity it is confluent with the sulcus cinguli by a short transverse fur- 

 row. The sulcus cinguli is made up of three parts superficially 

 confluent. Many branching fissures cut the marginal gyrus into 

 complex folds. Behind it is confluent with the subparietal com- 

 plex. The praecuneus presents a simpler arrangement than the 

 preceding area. The sulcus praecuneus is a single fissure with a 

 branching posterior extremity. The sulcus subparietalis is 

 arranged roughly in an " H " form with all segments connected. 



The cuneus is small and simply furrowed. There is an inci- 

 sura pariefo-occipitalis present, and the fissura parieto-occipitalis 

 begins as a single furrow at the border of the hemisphere and, rap- 

 idly deepening, extends downward without interruption into the 

 fissura calcarina, and indeed the anterior portion of the latter fis- 

 sure seems to be the continuation of the parieto-occipital. The 

 fissura calcarina seems to be a continuous fissure, but is divided, 

 by a bridging convolution reaching almost to the surface, into a 



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