201 



LESSON XXXVIII. 



STRUCTURE OF THE CEREBELLUM AND CEREBRUM. 



1. SECTIONS of the cerebellum across the direction of the laminae and vertical 

 to the surface. 



2. Section across the whole of one hemisphere of the cerebrum of a 

 monkey or man, passing through the middle of the third ventricle. 



3. Vertical sections of the cerebral cortex, one from the ascending frontal 

 gyrus, another from the occipital lobe, and a third across the hippocampal 

 gyrus and hippocampus. 



4. Transverse sections of the olfactory tract and bulb. 



In all these preparations make sketches under a low power of the general 

 arrangement of the grey and white matter, and also of the nerve-cells in 

 the grey matter. Sketch some of the details under a high power. 



The cerebellum is composed of a white centre, and of a grey cortex, 

 both extending into all the folds or laminae, so that when the laminae 

 are cut across, an appearance is presented of a white arborescence 



FIG. 236. SECTION THROUGH ONE OF THE HEMISPHERES OF THE CEREBELLUM, 

 TO SHOW THF, MEDULLAKY CENTRE AND ITS PROLONGATIONS INTO THE 

 LAMELLAE. 



covered superficially by grey matter. The white matter is in largest 

 amount in the middle of each cerebellar hemisphere (fig. 236). There 

 is here present also a peculiar wavy lamina of grey matter, similar to 

 that in the olivary body, and known as the nucleus dentatus (n.d.), 



