46 C. WINKLEE. THE CENTRAL COURSE 



myelinisation in foetal and young born animals, partly by studying 

 GOLGI preparations. 



I must avow, that I cannot support in every respect , the views 

 of FLECHSIG, who sets too much value on the signification of the 

 myelinisation-process in nerve-fibres. This method , though offering 

 great advantages, offers great dangers too. 



It may give evident results in some regards, as for instance, 

 that the vestibular-nerve receives the rnedullated fibres at an earlier 

 period of development than the cochlear nerve. But it may be very 

 venturous to ascertain , that the vestibular nerve is myelinisated at 

 a time when the cochlear is still quite exempt of rnedullated fibres. 



Investigators, who have worked exclusively with this method 

 will run a great chance to be induced into error, and it is my 

 opinion that FLECHSIG himself has not been very happy in his 

 description of the auditory tracts, especially in the separation of 

 the primary and secundary paths. The study of the development 

 of myelin may control other methods. Therefore it is of great value. 

 But it is restrained between strict limits and ought to be controlled 

 itself by the GoLGi-method and especially by the experimental 

 methods. 



The methods of experimental anatomy have been chiefly used 

 in my investigations, either the method of VON GUDDEN or that 

 of MARCHI. 



GUDDEN'S method of experimental secundary atrophy after lesions 

 in the young-born animal is, if exclusively used, dangerous, nearly 

 as dangerous as the myelinisation-method , but it cannot be totally 

 substituted by the methods of secundary degeneration , for instance 

 by the method of MARCHI. 



For an experimentally produced atrophy , once provoked , is 

 invariable. A nervous system sectioned in the young born animal 

 will be found totally atrophied after a lapse of three months or 

 longer. 



But the dangers of VON GUDDEN'S atrophy are evident. The method 

 is giving too little and too much. 



As soon as the atrophied fibres may be found distributed between 

 intact fibres , they are not recognised. The judgment on the par- 

 tially atrophied system is often a subjective judgment. In this respect 

 the method gives too little. 



Moreover nobody can foretell the extension of the atrophy in secun- 

 dary and even in tertiary systems consequent to the atrophy of the 

 insulted one. Neighbouring systems, completely independent of the 

 one damaged, may, under circumstances, atrophy. In all these 



