OF THE NERVUS OCTAVUS. 57 



The fibres mentioned here sub 3 are the ventral root-fibres par- 

 ticipating in the formation of the systema dorsale nervi octavi. 



In this way the Marchi-degeneration demonstrates that l e in the 

 stratum latero-dorsale corporis restifornie root-fibres are to be traced 

 us well from the cochlear, as from the vestibular nerve. They are 

 ranged there in such a manner, that distally the number of cochlear 

 fibres (dorsal root-fibres), proximally that of vestibular-fibres (ventral- 

 root-fibres) prevails. 



2 C that between the oval area and the radix spinalis N. V. prin- 

 cipally the fibres from the ventral may be traced. Only in the distal 

 regions there are found dorsal root-fibres'. 



3 e that in the corpus trapezoides thick fibres - - principally ventral 

 root-fibres - - as well as small fibres, mostly dorsal root-fibres, may 

 be pursued. 



c. The stfjj/jositioii that both roots send their fibres , though in 



different quantities , in the same paths , is confirmed by the 



study of the myelinisation of the roots in the rabbit. 



The Marchi-degeneration has shown us that the stratum latero- 

 dorsale is not only the continuation of the dorsal rootfibres, but 

 contains also ventral rootfibres (and as we shall see afterwards 

 many other secundary auditory fibres) , and that between oval area 

 and spinal quintus root enter root-fibres of both roots as well as 

 they do in the corpus trapezoides. 



These conclusions are not accepted by the authors, who have 

 studied the central distribution of the auditory nerve by means of 

 the myelinisation-method. 



So , for instance , the schema given by BECHTEREW is generally 

 accepted, and it is taught, that the ventral nucleus should be 

 an intervertebral nucleus, that the dorsal root may be continued 

 in the stratum latero-dorsale and the ventral root between the oval 

 area, of the restiform body and the spinal root of the nervus trigeminus-. 



And, basing on FLECHSIG'S investigations, it is usually taken for 

 granted that the corpus trapezoides only contains fibres of the 

 secundary auditory systems. Though these opinions are doubtless 

 in contradiction with many of the results, mentioned in the excel- 

 lent papers of HELD , they are usually defended on the continent. 



I must avow, that I fail to understand as yet, why the investi- 

 gators, who have studied the auditory system by means of the 

 myelinisation-method have not long ago stated the same conclu- 

 sions, that are defended here as the results of the Marchi-method. 

 For , as to my experience , the myelinisation of the root-fibres of 



