6o HUBER. [Vol. XVI. 



from the anterior root ; and now and then such a fiber could be 

 traced into a pericellular plexus of the simpler variety. 



Such observations, it seems to me, point conclusively to the 

 cerebro-spinal origin of the medullated fibers ending in the 

 ganglion in intra-capsular, pericellular plexuses. 



The non-medullated fibers seen in sections of a ganglion 

 wind their course through the ganglion between its constituent 

 cells. Many of these are no doubt the neuraxes of the sympa- 

 thetic neurons of the ganglion, although it is very seldom that 

 in section such fibers can be traced to a ganglion cell. This 

 may, however, now and then be done, as may be seen from 

 PI. IV, Fig. 12. Serial sections show further that some non- 

 medullated fibers enter the ganglia through the interganglionic 

 cords. Their mode of ending in the ganglia has not been defi- 

 nitely ascertained, unless possibly that shown in PI. IV, Fig. 17 

 (fibers c), and described with that figure, may be their mode of 

 ending. 



A brief summary of the observations made on the sympa- 

 thetic ganglia of Reptilia above described may here be given : 



i) The sympathetic neurons of Reptilia may be multipolar, 

 bipolar, or unipolar. The first two types need no further men- 

 tion. The unipolar cells, very characteristic for the sympathetic 

 ganglia of Reptilia, are relatively large, possessing one large 

 process, varying in length and its relation to the cell body of 

 the respective neuron. All these cells have one neuraxis, which 

 near the cell is non-medullated ; whether at some distance from 

 the cell it becomes invested with a sheath of myelin I am unable 

 to say. The neuraxis arises from the cell body or from some 

 one of the dendrites. The number of dendrites varies. The 

 cell body of all sympathetic cells of Reptilia is surrounded by 

 a nucleated capsule. 



2) Medullated fibers, no doubt of cerebro-spinal origin, end 

 in the ganglia, either in simple pericellular plexuses surround- 

 ing the multipolar or bipolar cells, or in more complex pericel- 

 lular plexuses with spiral fibers surrounding the cell body of the 

 unipolar cells. These pericellular plexuses are intra-capsular. 

 The medullated fibers branch in the ganglia, and may thus 

 influence a number of sympathetic cells through their several 



