752 



MOVEMENTS OF CORTICAL ORIGIN. [BOOK in. 



CO. 



Ivd 



FIG. 127. OUTLINE OF A TRANSVERSE DORSO- VENTRAL SECTION OF THE BIGHT 

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



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

 therefore intermediate between those shewn in Figs. 116 117 is introduced to 

 illustrate the course of the constituents of the pyramidal tract. 



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

 section. Pt. putainen, Op", Gp' the two parts of the globus pallidus of the 

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

 of Reil. 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 ; O.P. anterior part of the occipital 

 lobe. 



f.c. is the central fissure or fissure of Rolando. 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. 125, and the sagittal 

 figure shewn in Fig. 126. 



