THE HIND-BRAIN OR RHOMBENCEPHALON 



795 



a round bush, but has been aptly compared by Obersteiner to the branches of a 

 fruit tree trained against a trellis or a wall. Hence, in sections carried across 

 the folium the arborescence is broad and expanded; whereas in those which are 

 parallel to the long axis of the folium, the arborescence, like the cell itself, is 

 seen in profile, and is limited to a narrow area. 



From the bottom of the flask-shaped cell the axon arises; this passes through 

 the nuclear layer, and, becoming medullated, is continued as a nerve fiber in the 

 subjacent white substance. As this axon traverses the granular layer it gives off 

 fine collaterals, some of which run back into the molecular layer. 



Cell of Purkinje 



Molecular 

 layer 



Axons of 

 granule cells 

 cut trans- 

 versely 



Small cell \ A / 

 of mnlf.r.idar^ I ^V^" 



layer /}$ 



Basket cellj. 



Golgi cell 



^Nuclear 

 layer 



j Axon of cell of PurTcinfe 



Neuroglia cell 



Tendril fiber 

 Moss fiber 





FIG. 706. Transverse section of a cerebellar folium. (Diagrammatic,, after Cajal and Kolliker.) 



The internal rust-colored or nuclear layer (Fig. 706) is characterized by containing 

 numerous small nerve cells of a reddish-brown color, together with many nerve 

 fibrils. Most of the cells are nearly spherical and provided with short dendrites 

 which spread out in a spider-like manner in the nuclear layer. Their axons pass 

 outward into the molecular layer, and, bifurcating at right angles, run for some 

 distance parallel with the surface. In the outer part of the nuclear layer are some 

 larger cells, of the type II of Golgi. Their axons undergo frequent division as soon 

 as they leave the nerve cells, and pass into the nuclear layer; while their dendrites 

 ramify chiefly in the molecular layer. 



