DeWitt, Nerves in the Oesophagus. 383 



ammonium molybdate (Bethe (3) ), in which it was allowed to 

 remain for about twelve hours. The tissues fixed by the former 

 method were cleared and mounted in equal parts of glycerine 

 and the ammonium picrate solution ; those fixed by the latter 

 method were washed, dehydrated, cleared in xylol and either 

 mounted at once in balsam or embedded in paraffin and sec- 

 tioned, some transversely to the surface and others tangentially. 

 The second method of fixation was used especially to avoid 

 the maceration of the epithelium, which, after the continued 

 action of the ammonium picrate, was often so excessive as to 

 leave but little epithelium and hence but few of the termina- 

 tions of the nerves in the epithelium. 



Arrangements and 1 erminations of the Nerves in the muscular 

 coats. Between the circular and longitudinal muscular layers, the 

 nerve trunks, which, after ramifying in the outer connective 

 tissue sheath, have penetrated the longitudinal muscular layer, 

 form a coarse meshed plexus, at the nodal points of which 

 numerous nerve cells forming larger or smaller ganglia are 

 found. In the oesophagus of the rabbit and in the upper part 

 of the oesophagus of the cat, where striated muscle constitutes 

 the muscular coats, the ganglia are much smaller and less fre- 

 quent and contain relatively few nerve cells. The nerve cells 

 comprising these ganglia vary in size and shape. Most of them 

 are multipolar cells, each having' a round or oval nucleus, a dis- 

 tinct nucleolus, a granular and pigmented protoplasm, with 

 many dendritic processes and one neuraxis. The dendritic pro- 

 cesses are usually short and thick and break up into a large 

 number of branches which extend between the cells of the gan- 

 glion, forming a more or less intricate network, in the meshes 

 of which the nerve cells are sometimes enclosed. In the latter 

 case, we have an appearance like the "nidos pericellulares" de- 

 scribed by Ramon y Cajal (4-7) for the ganglia of Auerbach's 

 plexus of the intestinal canal, which Dogiel (ii) has shown to 

 be the result of an accidental enclosure of the cell, to be always 

 extra-capsular, and of less physiologic importance than was as- 

 signed to them by Cajal. Occasionally, as described by Dogiel 

 for the cells of the ganglia of Auerbach's plexus of the intes- 



