910 
ON THE DISTEEBTJTION OF NEEYES TO MUSCLE. 
oval swellings. At a and h are seen the jEine fibres which are continnous with 
the dark-bordered fibres. These are gradually lost amongst very fine fibres. 
The compound branches divide and subdivide on the surface of the muscular 
fibre. xTOO. 
c. Another fibre at a distance from the oval swelling, showing nuclei with 
very fine fibres ramifying upon the muscular fibres. X 700. 
Fig. 31. Dark-bordered nerve-fibre with fine fibres at the side of it. These fine fibres 
appear in one part like the outline of the tubular membrane, but at a short 
distance they are seen to give off branches which pass with other fine fibres. 
It will also be observed that there is no corresponding line on the other side 
of the dark -bordered nerve-fibre in this case. From bladder of frog. x700. 
It will be doubted by some if the fine fibres I have figured are true nerve-fibres ; but 
it must be borne in mind, (1) that dark-bordered nerve-fibres divide into fibres as fine as 
these in the trunks of the nerves near their distribution ; (2) that fibres as fine as these 
form the direct continuation of dark-bordered nerve-fibres themselves; (3) that all dark- 
bordered nerve-fibres terminate in fine fibres which divide and subdivide into finer 
branches which run in company with fine fibres apparently derived from the sheath of 
the nerve or from fibres external to the sheath, but which are probably true neiwe-fibres 
and, at least in some cases, are themselves but the continuation of dark-bordered fibres 
which run for some distance in the sheath and then diverge. 
