266 THE NERVOUS SYSTEM 



(b) Fibers from the anterior portion of the frontal lobe pass 

 through the anterior limb of the internal capsule and seem to 

 end in the gray matter of the pons and there to communicate with 

 the cerebellum through the middle peduncles. Fibers also pass 

 from the temporo-sphenoidal lobes and from the caudate nuclei 

 of the corpora striata to the cerebellum on the opposite side. 

 The connection is crossed in all these cases. 



FIG. 85. Diagram of the motor areas on the outer surface of a monkey's 

 brain. (Landois after Horsley and Schafer.) 



(c) Transverse fibers in the corpus callosum connect all parts 

 of the two lateral hemispheres. Besides these commissural fibers 

 there are those of the anterior and posterior white commissures. 

 Fibers in the anterior connect the tempero-sphenoidal lobes and 

 probably the corpora striata with each other; fibers in the pos- 

 terior connect the temporo-sphenoidal lobes with the optic thai- 

 ami of the opposite side. 



(d) The arcuate fibers connect different convolutions of the 

 same lobe and the convolutions of different lobes with each other. 

 Some of these are in the fornix, in the corpus callosum, and in 

 other parts, as well as running along the concave surface of the 

 cortex. 



