CONVOLUTIONS AND FISSURES OF SURFACE OF CEREBRUM. 49 



Observe now the region caudad of the central fissure and 

 above the temporal lobe. It is called the parietal lobe. It is 

 divided into a superior and an inferior parietal lobe by a sulcus, 

 which passes in a curve around the end of the fissure of Sylvius 

 and the end of the first temporal fissure, and is called the inter- 

 parietal fissure. There is nothing to mark the division between 

 the superior parietal lobe and the posterior central convolution, 

 unless, as often happens, a branch of the interparietal fissure 



FIG. 29. 

 Lateral view of the brain. For explanation, see Fig. 23. (After Ecker.) 



passes upward toward the margin of the hemisphere. In this 

 case, of course, the connecting convolution is much narrower. 



That part of the inferior parietal lobe which surrounds the 

 fissure of Sylvius is called the gyrus marginalis.* 



The part lying just back of this, and arching around the 

 end of the superior temporal fissure is called the gyrus angu- 

 laris. The former you will discover at once in every brain ; the 



* Marked "G. supra-marginalis" in the cut (Fig. 28). 



4 



