44 



diate continuation is often even more slender than the body 

 of the nerve fibril at a point midway between two nuclei. 



Further evidence that these delicate fibres are fine nerve- 

 fibres is seen in the fact of their continuation with the large 

 ganglion cells, and most conclusive proof in the fact that 

 they have been traced by Dr. Beale in continuation with 

 dark bordered nerve-fibres, and resulting from the subdivi- 

 sions of the axis cylinder of tbese. 



No ganglia are represented showing more than two cells, 

 for this reason, that, although cellular collections revealed 

 themselves under low powers resembling those indicated by 

 Dr. Beale as masses of ganglion cells, yet, as they could not 

 be resolved by high powers into individual bodies exhibiting 

 the characters of ganglion cells, I was unwilling to present 

 them as such. This difficulty may have been due to the 

 intensity of the staining, which was too vivid in the case of 

 many cells, all portions being alike deeply tinged, so that the 

 different parts could not be easily resolved ; nor, in aggrega- 

 tions, could the cells themselves be separated. Yet we 

 believe the fact of the existence of the ganglia is no less 

 established, at least until some more satisfactory interpreta- 

 tion is put upon them. 



These ganglia and nerves, apparently quite abundant in 

 the connective tissue of the notch of the young pig's kidney, 

 have also been found by Dr. Beale in the kidneys of children. 

 They are, however, more difficult to obtain in the adult 

 human kidney, probably in consequence of the increased 

 amount of formed material which rapidly grows at the ex- 

 pense of the germinal matter, rendering the latter more indis- 

 tinct and difficult of demonstration with increasing age. 

 This change is readily demonstrable by microscopic examina- 

 tion of the tendon of a child or young animal, in comparison 

 with a corresponding structure of an adult. The former will 

 be found crowded with nuclear or germinal matter, Avhile, in 

 the latter, it Avill be placed at longer intervals, separated 

 by larger quantities of the fibrous formed material now in 

 excess. Thus is produced a so-called connective tissue in 

 which uninjected capillaries and shrivelled nerve fibre, which 

 have performed their function, together with the more indis- 

 tinct ganglia and fibres still active, form a part. Hence it 

 is believed by Dr. Beale, that the oval masses of germinal 

 matter seen in the intervals between the tubes, and upon the 

 surface of the vessels of the mammalian kidney, belong to 

 nerve-fibres, the structure of which is so delicate, or so much 

 obscured, that it is extremely difficult to trace their course.^ 



• Beale, ' Kidney Diseases and Urinary Deposits,' 3rd edition, 1869, p. 

 17. 



