96 



Journal of Comparative Neurology. 



less frequently observed within the boundaries of the ganglion. 

 The fibers which pass to the dorsal branches from the ventral 

 root cross the greater mass of fibers which go to form the nerve 

 trunk' and this interweaving results in a tangle which renders a 

 sufficiently disassociated preparation quite difficult to obtain. 

 A few cases however have been found in which a ventral root 

 fiber was seen to split into two. That one of these passed 

 to the dorsal branches could not be clearly determined owing 

 to injury in the disassociation ; that they were ventral root 

 fibers, however, there is no question. This splitting of ventral 

 root fibers is not included in the possibilities suggested by 



Gaule. 



As to the splitting of fibers arising from the cells of the 

 spinal ganglion, while many divided fibers have been observed, 

 none have yet been seen concerning which it can satisfactorily 

 be asserted that both the products of the division pass to the 

 periphery. Unless each can be followed separately either into 

 the nerve trunk or into the dorsal branches there is nothing to 

 show that the structure is not the characteristic T-fiber, or one 

 of the numerous divisions which Dogiel claims for the processes 

 of his ganglion cell of the Ilnd type. However it must be re- 

 membered that the investigation is only just begun. But it 

 should also be remembered that an occasional division of the 

 peripheral process of the spinal ganglion cell has already been 

 noted by previous observers. 



3. The possibility to be suggested by Scheme IV is that 

 among the spinal ganglion cells which never send processes to 

 the dorsal root, there are some which send processes to the 

 periphery. 



There are no histological observations which directly sup- 

 port this scheme. The investigations of Hodge ('89) and 



