94 THE CEREBRUM. 



end of the corpus callosum; there it is bounded on its convexity 

 by the subparietal sulcus (Fig. 28). Underneath the corpus 

 callosum, the anterior end of the gyrus cinguli is continuous with 

 a small vertical gyrus, called the area par ol] actor ia (Brocae), 

 which is embraced between the anterior and posterior parol- 

 factory sulci and is continuous with the area of the same name 

 on the base of the cerebral hemisphere. This part belongs to 

 the cortical area of smell. The posterior end of the callosal gyrus 

 is almost separated from the hippocampal gyrus by the anterior 

 calcarine fissure; the narrow link left between this fissure and the 

 splenium of the callosum is the isthmus gyri fornicati. It is 

 claimed by Schafer and others, that the superior part of the gyrus 

 cinguli constitutes a portion of the somaesthetic area; but the 

 histological investigations of Dr. A. W. Campbell appear to dis- 

 prove such a claim. According to Paul Flechsig, the gyrus cinguli 

 contains the center of taste. He locates the center in the posterior 

 part of the gyrus adjacent to the splenium of the corpus callosum; 

 it forms a thin zone bounding the callosal sulcus (Fig. 55). 



The gyrus hippocampi (Figs. 26 and 28) extends downward 

 and forward, along the hippocampal fissure, from the isthmus 

 to within a half-inch of the temporal pole. Its anterior extremity 

 is separated from the pole by the ectorhinal sulcus, and is bent 

 upward and backward over the end of the hippocampal fissure, 

 forming a sharply curved hook, the uncus. The hippocampal 

 gyrus is bounded below and laterally by the collateral fissure. 

 Posteriorly, it is continuous with the gyrus lingualis. The reflected 

 part of the uncus hippocampi is continuous with a concealed 

 gyrus, located between the hippocampal and chorioidal fissures, 

 viz., the dentate fascia; a narrow band, which winds over the 

 uncus near its free point and is called the frenulum of Giacomin 

 establishes this junction with the dentate fascia. 



The uncus and the area parolfactoria constitute the greater 

 part of the receptive center of smell (Figs. 55 and 57). In the 

 uncus anterior to the end of the hippocampal fissure, Retzius 

 locates the gyrus circumambiens and gyrus semilunaris, which 

 he has identified in the human embryo; and he declares them to 

 contain the end of the lateral olfactory stria and of the gyrus 



