Chapter II. 



On the distribution of the nervus octavus in the central 

 nervous system in rabbits. 



I. Methods of investigation. Introduction. 



In order to investigate the central distribution of the nervus 

 octavus it is necessary to use several methods of investigation. 



From different species of animals the normal central nervous 

 system must be compared, before beginning the researches in rab- 

 bits. Though this method of comparative anatomy need not be 

 extended so far, as to apply it to nearly all vertebrates, it is neces- 

 sary to examine the medulla oblongata of men, dog, cat, horse, 

 mouse, rabbits, the amphibia and birds, which are common in our 

 laboratoria, before examining foetal or experimentally prepared 

 material of one species. 



I even believe, that many questions, touched in this paper, will 

 ask for a solution from the comparative anatomy of special animals 

 or even of species , where an irregular differentiation of functions 

 may be supposed. So for instance the examining of the medulla 

 oblongata of the mole , the squirrel , the bat , of the cetacea, may 

 teach us much about the auditory nervous system. But for my 

 purpose the method of comparative anatomy is occupying only a 

 second plan. My purpose aims the study of the N. octavus in 

 rabbits. Therefore the method of comparative anatomy has the value 

 of an introductory method, but other methods are more necessary. 

 Absolutely necessary are embryological-investigations. 



They may be applied in different ways, partly by studying the 



