CAPSULA INTEENA, COHPUS STRIATUM, INTERBHAIN-GANGLIA. 



251 



meet has been named the genu (knee) of the internal capsule. Impress this 

 peculiar angular form of the capsula interna well upon your memory. The 

 relation of the separate parts of the corona radiata to the two limbs, or 

 .segments, is probably approximately constant, and therefore exceedingly im- 

 portant clinically. In the posterior limb, for the most part near the genu, 

 lie the fibers running from the motor zone to the extremities (pyramidal 

 iract). Just in front of them are the tracts which stand in relation with 



Fig. 162. — Frontal section through the forebrain, close behind 

 the pillars of the fornix. 



the nuclei of the facialis and hypoglossus, and which arise from the lower 

 •end of the anterior central convolution. 



Behind the pyramidal tract the tracts designated as the tegmental 

 radiation are met with in about the last third of the posterior limb, or some- 

 what more anteriorly. Adjoining these posteriorly lies the tract from the 

 ■occipital lobe to the origin of the opticus. According to clinical facts, there 

 must also be fibers in this region which pass from the cortex of the temporal 

 lobe to the nucleus of the acusticus, and also fibers which stand in some 

 relation to the sense of smell. Thus there meet, in the posterior third of the 



