338 S. W. RANSON AND P. R. BILLINGSLEY 
the ganglion where ‘‘they are found branching and rebranching, 
and forming, with the dendritic processes of the ganglion cells, 
what Dogiel has described as the intercellular plexus.’? Huber 
quotes with approval the conclusion of Dogiel (95): “Die feinen 
Fasern, welche in den Ganglien mit intercellularem Geflechte 
endigen, zu den sympathischen, augenscheinlich vorzugsweise 
markhaltigen Fasern gehoren.”’ It is interesting to note that 
Huber was able to trace some of the fine unmyelinated fibers of 
this plexus to definite endings on neighboring dendrites. 
According to Dogiel (95), whose observations were made on 
the terminal ganglia, the finer myelinated and unmyelinated 
fibers enter the ganglion, branch and intertwine, and break up 
into fine branches which cross in various directions and finally 
break up into finer fibers of uncountable number. These form 
a thick plexus among the cells and at the periphery of the ganglion. 
The fibers of the plexus are in contact with the dendrites, but 
separated from the cell bodies by their capsules. All the fibers 
of the plexus are beset with varicosities. 
Michailow’s (11) conception of the intercellular plexus differs 
from that of the two preceding authors in that, according to him, 
the constituent fibers of the plexus anastomose with each other 
forming a closed network. By means of this network all or at 
least many of these fibers are united together, one neurone being 
in this way united with many others. As will be seen later, there 
are good reasons for discarding this part of Michailow’s descrip- 
tion of the intercellular plexus. 
In preparations of the superior cervical ganglion of the cat or 
dog by the pyridine silver method one can readily see a plexus of 
fine unmyelinated fibers running among the cells in every direc- 
tion through the ganglion (fig. 10). The dendrites are not well 
stained in these preparations and only their coarser branches are 
visible. The finer dendritic ramifications, which, according to 
those who have worked with the methylene blue stain, help to 
form the intercellular plexuses, are not to be seen. In these 
preparations the network of fibers under discussion corresponds 
only to the axonie constituents of the intercellular plexuses of 
Dogiel and Huber. 
