— 71 — 
wiss. Zool. Bd. 35) but at the same time he, himself, does not seem 
to know the papers by Bellonci on the nervous system of inverte- 
brates, which woLild seem to be of even higher importance to his 
investigations. 
I think it is, indeed, also very strange, that neither Rawitz nor 
Haller (nor most modern writers) are acquainted with the exellent 
papers on the central nervous system of vertebrates by GoLGi; 
they quote a great many other and less important writers, but they 
do not seem to know this eminent histologist who, in my opinion, 
has really introduced a new epoch in our researches into the struc- 
ture of the nervous system.') 
If we look back at this review of the literature and compare 
the statements of the various authors with the results of my in- 
vestigations, it will be seen that in most respects, and these also the 
principal ones, I can scarcely agree with any of them; the author to 
whose views I feel most related is Leydig. As to the nerve-tubes 
and ganglion cells, we have seen that almost all writers, except 
Leydig, who describe a fibrillar structure suppose the nerve-tubes 
to consist of nervous fibrillæ and inter fibrillar substance, and in the 
ganglion cells most of them describe a similar structure, whilst some 
writers describe a reticulation. Only Leydig has decisively expres- 
sed himself in favour of the »interfibrillar substance«, hyaloplasm, being 
the real nervous substance, whilst the fibrillæ should belong to a sup- 
porting substance, spongioplasm. As to the dotted substance, we have 
seen that most writers who have seen a reticulation or fibrillæ etc. 
in it, have agreed in calling the reticulation a nervous one, and the 
fibrillæ nerve-fibrillæ. Some writers have certainly described a nervous 
reticulation as well as a reticulation of connective-tissue, but Leydig 
is the only writer who has decisively said that the whole reticulation 
w^as of supporting nature, and that the real nervous substance was 
the homogeneous one extended in the cavities of the reticulation. 
Though I do not agree with Leydig, he is, however, the author to 
whose views my observations are most related, the points in which 
we essentially differ will be seen in the description of my investigations. 
^) Haller certainly qiiotes from Unger a paper by Golgi, this is, however, 
an old paper (1872) and is relatively of but little importance when compared with 
Golgi's later publications. 
