THE NERVOUS SYSTEM 



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lateral regions of the cerebellum present a complicated appear- 

 ance owing to the contortion of the folia, which results from 

 the unequal development on its sides of the several lobes. In 

 its total size the cerebellum keeps step with the cerebrum, 

 the right side of one organ being associated with the left side 

 of the other. 



FIG. 23. VERTICAL SECTION OF THE CORTEX OP THE CEREBELLUM, CUT PARALLEL WITH THE 

 LONQ Axis OP A FOLIUM. 



A shows three cells of Purkinje, their espalier systems of dendrites being seen in profile. A 

 " mossy fibre " enters the granular layer from the white matter. About a dozen of the 

 granules are shown, each with four or five dendrites and a single axon. The axon bifur- 

 cates in the molecular layer, its two branches running for a considerable distance to left 

 and right along the folium. B shows the other nervous elements which are found in the 

 cortex : a cell of Golgi with a ramified axon, a climbing fibre, a basket-cell, of which the 

 axon divides into four branches, and a small stellate cell. 



The grey matter which covers the surface of the cerebellum, 

 its cortex, is singularly regular in microscopic pattern (Fig. 23). 

 It is divided into three sheets : superficially, the molecular 

 layer in which the dendrites of the cells of Purkinje branch ; 

 beneath this, the thin layer in which are situate the cell-bodies 

 of these neurones ; thirdly, the layer of small cells, or granules. 

 Cells of Purkinje and granules have been already described 



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