112 Journal of Comparative Neurology. 



the meduUated fibers in the sympathetic ganglia divide into 

 branches, from which collateral branches (as a rule non-medul. 

 lated) are given ofif, so that, as Dogiel (25) has pointed out, a 

 single medullated fiber may end, according to the number of 

 collateral branches present, in a number of peri-cellular baskets. 



(b). Birds. In birds (chicken) the peri-cellular baskets in 

 the sympathetic ganglia have essentially the same structure as 

 those found in mammalia, and are also the endings of medul- 

 lated fibers in the ganglia. The fibrillae of the network form- 

 ing the perl-cellular baskets in birds are on an average somewhat 

 finer and not so numerous as in mammalia, so that as a whole 

 the baskets are somewhat simpler. They are always intra-cap- 

 sular. In Fig. 8, b, are shown two ganglion cells from one of the 

 dorsal sympathetic ganglia of a chicken, where a small vari- 

 cose fiber breaks up into two branches, each of which ends in a 

 peri-cellular basket. 



(c) Reptilia. In the tortoise the structures in question 

 vary greatly in complexity. Many of the peri-cellular baskets 

 resemble in structure those found in sympathetic ganglia of 

 mammalia and birds ; this is more especially the case in the 

 smaller ganglia — the cardiac ganglia and the smaller ganglia of 

 the chain. The cells enclosed in such baskets are usually mul- 

 tipolar, resembling in shape those found in mammalia and birds. 

 But, as previously stated, many of the sympathetic neurons of 

 reptilia (and this is more especially true of the larger ganglia) 

 are relatively large and of peculiar form. The cell body of such 

 neurons may be round or oval, and from it springs one large 

 process, which may be straight or twisted around the cell body 

 or upon itself. In either case, it breaks up at a variable dis- 

 tance from the cell body into several large branches one of 

 which becomes a neuraxis, the others being dentrites. The 

 peri-cellular baskets found enclosing such cells are nsually much 

 more complicated than those found about the multipolar cells, 

 above described. The medullated fiber ending in these more 

 complex baskets is often wound spirally around the neuraxis of 

 the sympathetic cell, and about the large process from which 

 the neuraxis springs, before breaking up into the fibrillae form- 



