NERVUS TERMINALIS: MAMMALS 29 



together with the peripherally directed process of the cell, sug- 

 gests that it pertains to the sympathetic system. Its small size 

 favors this interpretation. 



The largest unipolar cell observed (fig. 10) was also the only 

 one of this type found which was binucleated. The process was 

 of large diameter and did not stain so dark as did the majority 

 of fibers. It was not possible to follow it beyond its point of 

 entrance into the bundle of smaller black fibers of which it 

 became a part. The large size, both of cell and of cell process, 

 resembles somewhat the large unipolar cells found by Carpenter 

 ('12) in the ciliary ganglion of the sheep. 



Unipolar cells were not numerous and were found only in the 

 smaller ganglia. Whether their presence in the larger ganglia 

 was hidden by the crowded condition of these could not be de- 

 termined. It seems, however, that the latter are composed 

 principally of multipolar cells, with fairly numerous bipolar cells 

 near their peripheries. 



(b) Bipolar cells. Cells of this type are quite numerous, both 

 in the smaller ganglia and in the larger ones. A number of such 

 cells isolated from other nerve cells were also found. Figure 6 

 represents two typical bipolar cells from the periphery of the 

 largest ganglion (fig. 3, gn.) of the left nervus terminalis of a 

 kitten of two weeks. The processes of these, which are of large 

 size, took only a brownish tinge from the impregnation. A few 

 fibers of small size which stained black were present in the im- 

 mediate neighborhood of these cells and are indicated in the 

 figure, as are also some large unmyelinated fibers. These are 

 doubtless fibers of similar bipolar cells. A few relatively small 

 bipolar cells were found, one of which is shown in figure 5 (bix.). 

 The processes of these were quite slender and stained black. 

 They were followed for some distance, but no conclusive evi- 

 dence as to their terminations was obtained. 



The isolated bipolar cells above noted were found in the course 

 of small strands of fibers, between the nodal points where several 

 such strands converge (fig. 8). A few were found on the walls 

 of blood-vessels or near them. One of these is illustrated in fig- 

 ure 7, in which also is shown an unmyelinated fiber of small size 



