236 THOMPSON YATES LABORATORIES REPORT 
In the muscular system as a whole the changes were of the ordinary character. In the 
gastro-cnemius very few muscle-fibres remained ; the rest were entirely replaced by fat. In other 
muscles many fibres were atrophied, but some were distinctly hypertrophied. Most of them 
showed signs of alteration in the surrounding connective tissue, varying from a proliferation of 
nuclei of the sarcolemma to a deposit of fibrous tissue around the fibre. Several fibres had a 
distinctly hyaline appearance, and a few showed vacuolation. 
The muscle-spindles were for the most part unaffected, but in a few there was a 
diminution in size of an intrafusal fibre, with a deposit of hyaline material around. The nerve- 
fibres supplying them were apparently healthy. In some muscles, c.g.^ gastro-cnemius, I could not 
find any spindles in the sections examined. 
Sherrington has shown that division of the nerve supplying a muscle will not produce 
atrophy or degeneration of the muscle-fibres within the spindle. The muscle itself may be totally 
Fig. 2 
The same with afFected fibre. 
atrophied, and every nerve-fibre going to it have disappeared, yet the muscle-fibres within the 
spindle remain intact ; the muscle-spindles are all that are left of the original muscle. 
It would therefore appear highly probable that any pathological alteration in such fibres 
is primary, and, consequently, also primary in the other ordinary fibres, although commencing much 
earlier in them. So that, so far as it goes, my observation supports the now generally accepted 
theory of the intra-muscular origin of the disease. 
This theory is also supported by the facts that generally no nervous changes have been 
detected in the cases examined, and the connective tissue changes do not appear to cause atrophy 
by compression, for where there is much connective tissue there is a total increase in the size of 
