COS 



THE NEEVOUS SYSTEM 



into two coarse branches, which each divides dichotomously into a suc- 

 cessiua of increasingly more delicate branches forming peripherally a 

 dendronic field of extreme profusion of non-anastomosing fibrils. The 



dendron viewed as a whole constitutes a fan- 

 shaped structure. Its expansion is in a 

 plane at right angles to the long axis of the 

 convolution. In sections parallel with the 

 long axis of the convolution the dendronic 

 field is very narrow, and never wider than 

 the diameter of the cell-body. 



The basket-cells, or large cortical cells, 

 are multipolar elements with relatively 

 short robust branching dendrons, and a 

 long axon which passes horizontally in the 

 same plane in which the dendronic expan- 

 sion of the Purkinje cells are placed. Along 

 its course it gives off five or six collaterals 

 which, as also the post-collateral portion 

 of the axon itself, pass .centrally toward the 

 Furkinje cells where each breaks up into a 

 profuse terminal arborization which invests 

 the cell-body in the manner of a 'basket.' 

 The basket cells occupy the middle and 

 outer portions of the molecular layer; they 

 are apparently of the nature of association 

 neurons, perhaps coordinating the function 

 of a number of Purkinje cells. 



The small cortical cells are distributed 

 throughout the molecular layer but are more 

 abundant in the outer half. They are mul- 

 tipolar and vary considerably in size, some 

 being almost as large as the basket cells. 

 They possess from two to five delicate den- 

 drons distributed for the most part in the 

 same plane as those of the Purkinje cells. 

 Their short slender axon, which is horizon- 

 tally placed, is frequently characteristically 

 looped. The axon of some of these cells has numerous collat- 

 erals. 



The nuclear or granular layer also contains three distinct types 



FIG. 526. A PURKINJE CELL 

 FROM THE CEREBELLAR 

 CORTEX OF THE RABBIT. 



Highly magnified. 

 Nissl.) 



(After 



