128 THE PHYSIOLOGY OF MUSCLE AND NERVE. 



uniform; atrophy rather than degeneration is the change that is 

 prominent, and this atrophy in some neurons occurs early, while 

 in others it is apparent only after a long interval of time. An 

 explanation of this variation in the reaction of the nerve cells 

 and their disconnected central stumps cannot yet be given. On 

 the peripheral side of the section, as stated above, the degenera- 

 tive changes are prompt and complete and affect all of the fibers.* 



'*Nissl, "Allgemeine Zeitschrift f. Psychiatrie," 48, 197, 1892. Also 

 Bethe, loc cit., and Ranson, "Retrograde Degeneration in the Spinal Nerves," 

 The Journal of Comparative Neurology and Psychology, 1906, 16, 265. 



