648 



PHYSIOLOGY. 



hippocampal gyrus ends inferiorly in a crochetlike extremity, termed 

 the uncus. The gyri f ornicatus and hippocampus together form the 

 great limbic lobe; the marginal convolution is merely the internal 

 aspect of the convolutions of the frontal and parietal lobes. That 

 portion which forms the mesial aspect of the ascending frontal con- 



Fig. 256. Thalamus and Corpora Quadrigemina Seen from the Side. 



(EDINGER.) 



The forebrain removed at the point where its coronal fibers pass into the 

 capsula interna. The relations of the optic radiation to the posterior part of the 

 capsula interna and to the point of origin of the opticus are shown diagram- 

 matically. Bindearm, Peduncle. Fuss, Pes, or crusta. Hint. Arm., Posterior 

 brachium. Stabkranz zu den Optic Centr., Coronal fibers to the optic centers. 

 V. Arm., Anterior brachium. 



volution is known as the paracentral lobule. Upon the mesial aspect 

 of the postero-parietal lobule is a quadrilateral lobule : the prascuneus. 



Between the parieto-occipital and calcarine fissures is a wedge- 

 shaped lobule called the cuneus. 



Structure of the Cerebral Convolutions. The gray matter of the 

 cerebral cortex has been divided into four layers : 



