8 Journal of Comparative Neurology. 



himself. Yet not long ago an article of Smirnow's (6) appeared, 

 also an investigation of these elements of the cerebellum of 

 man, as well as of the dog and hare. The results brought the 

 author to the conclusion, in opposition to Stohr's view, that two 

 distinct kinds of cells are to be distinguished in the molecular layer 

 according to the behavior of tJie axis-cylifider. The figures given in 

 this work appear to me also to plainly show that there are cells 

 in the molecular layer whose axis-cylinders do not bear compar- 

 ison with those of the cells hitherto described as '^ basket cells." 

 In a number of these cells (in man also) the nervous process a 

 short distance from its origin breaks up into numerous terminal 

 arborizations which may be distributed in all directions. The 

 field of distribution of many of these axis-cylinders does not ex- 

 tend down to the bodies of the Purkinje cells and if certain iso- 

 lated branches do come into the neighborhood of the latter, yet, 

 in view of the distribution in many directions of the remaining 

 branches, this is to be regarded as an incidental appearance. 

 The tassel-like arborization of the collaterals so characteristic of 

 the basket cells can nowhere be demonstrated, at all events, 

 with these cells. There appears, after all, to be only one char- 

 aateristic applicable to all the cells of the molecular layer, viz. : 

 that their axis-cylinders soon break up into their terminal arbonza- 

 tions and geiierally do not leave the region of the molecular layer. 

 The special behavior of the axis-cylinders of the individual cells, 

 however, that is the definite relations of some to the bodies of 

 the Purkinje cells and the correlated typical adaptation of the 

 terminal arborizations to the latter and the entirely disorderly 

 mode of distribution of otJier cells, compels, or at least entitles 

 us, in agreement with the conclusion of Smirnow previously 

 given, to distingtnsh two kinds of cells in the molecular layer, i. e. 

 ^'basket cells" and the others accurately described by Smirnoiv 

 which we still for the present may term ' ' small cortical cells. " It 

 is not thereby rendered necessary to create 2. fundamental dis- 

 tinction between these two categories of cells. It even appears 

 probable to me that the basket cells are merely to be regarded 

 as a specialized fonn of the molecular cells. Nevertheless the 

 morphological differences in the behavior of the axis-cyhnder 



