98 JoiKNAL OK CoMl'AKATUlC NkUK()LO(;V. 



(r) sporadic cells, especially in proximity to the lateral 

 columns. 



The ganglion cells of the anterior cornua usually send 

 their processes directly or indirectly either to the ventral 

 roots or a medullary column; a considerable number, how- 

 ever, may be followed through the ventral commissure to the 

 columns of white matter of the opposite side. I have also 

 observed cases where the cells of the ventral cornu of one 

 side send processes through the ventral commissure to the 

 fibres of the ventral columns of the other side. The above 

 course is pursued by most of the fibres from a group of cells 

 laterad to the canalis centralis, though some of the fibres pass 

 to the lateral columns of the opposite side. 



Those cells which occupy that part of the gray matter 

 adjacent to the lateral column send their process, for the 

 most part, to that column, but a part of the fibres pass 

 to the other side. 



In seeking examples of undoubted motor cells, only such 

 as show an evident direct connection with a ventral root 

 could be safely chosen. In these cases a remarkable peculi- 

 arity consists in the fact that their fibres, generally before 

 entering the nerve root, give off' a certain number of exceed- 

 ingly delicate fibrils, which curve toward the ventral part of 

 the gray substance and fuse with the complicated nervous 

 reticulum existing there. "The motor cells then stand 

 in immediate but not isolated connection with a nerve fibre." 



The dorsal nerve roots consist solely of fibres whose axis 

 cylinders enter the gray substance and there subdivide and 

 assist in forming a diftuse reticulum. 



[It should be stated that Lenhossc-k has showed. July, 

 1890, that fibres arising from cells in the lateral part of the 

 ventral cornu pass through the dorsal roots and through the 

 spinal ganglion without entering into connection with cells of 

 this ganglion.(') — C. L. H.] 



I Anatomischer Aiizeiger, 1890, Nos. 13 .incl 14. 



