988 



FIBKES OF THE PEDAL SYSTEM. [BOOK in. 



fc 



FIG. 123. 



OUTLINE OF A TRANSVERSE DORSO-VENTRAL SECTION OF THE RIGHT 

 HALF OF THE BRAIN. (Natural size.) (Sherrington.) 



The section which is taken at the level of the knee of the capsule and is therefore 

 intermediate between those shewn in Figs. 116117 is introduced to illustrate 

 the course of the constituents of the pyramidal tract. 



O.T. optic thalamus ; N.c. nucleus caudatus, the head only appears in this section. 

 Pt. putamen, Gp", Gp f the two parts of the globus pallidus of the nucleus 

 lenticularis ; C. the claustrum; C.E. the external capsule; In. the island of 

 Beil. c.a., the anterior commissure shaded to render it distinct and the fibres 

 from the temporo-sphenoidal lobe which pass into it being indicated by broken 

 lines. Op. the optic tract ; Ivd. the end of the descending horn of the lateral 

 ventricle ; F. the fornix ; F'. the end of the anterior pillar of the fornix in the 

 base of the thalamus ; c.c. corpus callosum ; OP. anterior part of the occipital 

 lobe. 



/.c. is the central fissure or fissure of Eolando. The course of the fibres of the 

 pyramidal tract connected respectively with the trunk, leg and arm, and hence- 

 with spinal nerves, and of those connected with the face and hence with 

 cranial nerves, is shewn by broken lines. These are all seen converging into 

 the internal capsule C.I. This figure should in respect to the course of these 

 fibres be compared with the horizontal section shewn in Fig. 121, and the 

 sagittal figure shewn in Fig. 122. 



