CHAPTEK XLIL1 



THE BRAIN 



A STUDENT'S first glance at a brain, or at such a drawing of it as is 

 given in fig. 453, will be sufficient to convince him of its complicated 



FIG. 453. Base of the brain. 1, superior longitudinal fissure ; 2, 2', 2", anterior cerebral lobe ; 3, fissure 

 of Sylvius, between anterior and 4, 4', 4", middle cerebral lobe ; 5, 5', posterior lobe ; 6, medulla 

 oblongata ; the figure is in the right anterior pyramid ; 7, 8, 9, 10, the cerebellum; +, the inferior 

 vermiform process. The figures from I. to IX. are placed against the corresponding cerebral nerves ; 

 III. is placed on the right crus cerebri. VI. and VII. on the pons Varolii ; X. the first cervical or 

 suboccipital nerve. (Allen Thomson.) . 



structure. We shall devote this and a few succeeding chapters to 

 anatomical considerations, before passing on to the study of its 

 physiology. 



