TO THE ELEMENTAET EIBEES OF STEIPED MUSCLE. 
613 
materially in certain cases. This seems to depend in some measure upon the state of 
the muscular fibre itself. If it is contracted, the nerve-fibres appear much wider than 
in cases where the muscle is relaxed and the fibres stretched to their full extent. The 
nerve-fibres undergo change very soon after death, and the finer ramifications seem to 
be completely destroyed by alkalies. Unless the tissue be properly preserved very soon 
after the death of the animal, it is not possible to demonstrate the arrangement 
described in this paper. The delicate structure very soon becomes destroyed by the 
action of air or water, and nothing is to be seen but a few oil-globules and a little 
fibrous-like structure. 
The nerves of muscle freely divide and subdivide before they reach their ultimate 
distribution, as was demonstrated by Wagner and others. I have observed that many 
of the ultimate fibres w’hich appear to be single, really consist of two or more fibres in 
close apposition, which vary much in their diameter. Where one fibre is wide, its 
neighbour is reduced to a very thin cord. A little further on the diameter of the latter 
increases, while that of the former becomes reduced in a corresponding degree. A fibre 
passing into a trunk at right angles is frequently seen to divide into two branches which 
become lost in the trunk, but may be seen to pursue their course in opposite directions. 
The finest ramifications upon muscle are thin and flattened, as may be seen at points 
where the nerves pass round one elementary fibre to reach the surface of another. 
0ml Bodies or Biiclei. 
In connexion with all nerve-fibres, there are little oval corpuscles which are readily 
coloured by carmine. These are the nuclei of authors, and are essential constituents of 
the nerves, especially towards their peripheral distribution. They are soft in the recent 
state, and, in my preparations, have a granular appearance under the highest powers of 
the microscope. They contain two, three, or more distinct globules, with a clear out- 
line and transparent centre, the so-called nucleoli. In ordinary dark bordered nerve- 
fibres, these bodies for the most part appear to be situated outside the white substance 
(nuclei of the tubular membrane) ; but in some nerves they may be seen in the wdiite 
substance itself, and occasionally in connexion with the axis cylinder. As the nerves 
approach their distribution these bodies increase in number, and undoubtedly form an 
integral part of each separate fibre. They are often equal to the fibre in width, and 
sometimes they appear even wider, but this is probably due to stretching and alteration 
in the fibre itself. In bands composed of from five to eight or nine fibres, in the mouse, 
they are more than the thousandth of an inch apart, but in some of the terminal fibres 
they are as close as the two-thousandth of an inch. Not unfrequently four may be 
seen close together upon the surface of an elementary fibre. 
After gmng a full description of the corpuscles imbedded among the fibrillse, as can 
be easily demonstrated in the large primitive fibres of the frog, Mr. Bowman states that 
in one instance he observed similar corpuscles on the exterior of a fasciculus in the 
chrysalis of the tiger-moth, but the relations of these were doubtful. He also noticed 
