THE CEREBELLUM OF AMBLYSTOMA 271 



the Golgi cells of Type II, but the sparsely branched axone would 

 exclude them from this group. 



In position and size as well as in general characteristics, these 

 cells appear to correspond more closely than do the larger ones 

 first described to the reduced Purkinje cells found by Herrick in 

 Necturus. Various transitional stages between these reduced 

 cells and the more highly differentiated ones were observed. The 

 degree of morphological differentiation appears to correspond 

 roughly with the position of the cell. Those located at the cere- 

 bellar border are the most simple in type; cells at various levels 

 in the granular layer appear to be somewhat more advanced, 

 while the cells composing the Purkinje cell layer most closely 

 resemble Purkinje cells of higher forms (figs. 8 to 13). Not all 

 preparations revealed the presence of these reduced cells, but 

 this was probably due to the idiosyncrasy of the Golgi technique. 

 When present in a given series of sections they were more numer- 

 ous than the larger cells more deeply placed. They were found 

 in greatest number along the cerebellar border about midway 

 between the median line and the lateral border of the cerebellum, 

 but many were observed quite close to the median plane and 

 also laterally, and at various levels between the cerebellar border 

 and the Purkinje cell layer. They might be considered to belong 

 to the granular layer of the cerebellum, but because of their ap- 

 parent relation to the cells of the Purkinje cell layer they are 

 described at this point. 



The granular layer, in addition to the reduced Purkinje cells 

 just noted, consists of numerous small rounded cells, among which 

 are interspersed myelinated fibers. In Golgi preparations these 

 cells are seen to possess several relatively short, tortuous processes 

 which give a stellate appearance to the cell. Many of these 



Fig. 12 Horizontal section through cerebellum of Amblystoma tigrinum. 

 Series CXVII, si. 3, sect. 2. Golgi method. X 60. 



Fig. 13 Horizontal section through cerebellum, deeper than that of figure 12. 

 Series CXVII, si. 3. Golgi method. X 60. 



Fig. 14 Horizontal section through cerebellum of Amblystoma tigrinum, 

 showing various elements of granular layer. Series CCIV, si. 3, sect. 83. Golgi 

 method. X 196. 



