— 102 — 
seen in the nerve-tubes. My opinion upon this point is, that this reti- 
culation is, to some extent, a real one having partly a quite spongy 
structure without the formation of tubes; to some extent the latter 
must, however, also be the case, as we shall soon see. The substance 
forming the reticulation has, as mentioned, a great resemblance to 
the sheaths of the cells as regards its staining etc, and it is, in my 
opinion, the same substance which forms the sheaths of the primi- 
tive tubes in the nerve-tubes, viz. spongioplasm. 
Before we subject the significance of this substance to a further 
examination I think it will be well to look somewhat at the struc- 
ture of the processes of the ganglion cells and their origin in the 
cell-protoplasm. 
The contents of the xorocesses, tvithin the cell, its 
structure and origin in the cell-pr otoplasm. — The gangUon 
cells of the lobster are, as a rule, imipolar; if they have several 
processes, there is always one of the process which has a special 
appearance, and which is the real nervous process; if other processes 
are present they are, as I call them, protoplasmic processes, and 
they have, in my opinion, a nutritive function, as will be subse- 
quently mentioned. At present we will only consider the structure 
and origin of the nervous process. 
In well prepared sections, a distinct longitudinal striation of these 
processes is easily observed. On observation of transversally trans- 
sected processes, it is seen that .this striation is produced by primi- 
tive tubes having the same structure, and constituting the nervous 
processes in the same way, as described of the nerve-tubes. 
As regards the staining, the contents of the nervous processes 
differs from the protoplasm of the ganglion cells; the latter having 
generally a much darker staining. This difference is, for instance, 
very prominent in fig. 37 & 38, where the contents of the longitu- 
dinally transsected processes have a very light staining and a distinct 
striation. 
The origin of the nervous processes differs somewhat in the 
various cells. In fig. 26 it has the appearance, as if the contents of 
the nervous process arises from a convergence of primitive tubes from 
the whole body of cell-protoplasm, in which they have a uniform 
extension, and to which they generally give, to some extent, a con- 
1) I have in reality, never observed a multipolar ganglion cell of quite in- 
dubitable multipolar shape, in the nervous system of the lobster. I am afraid that 
it has very often been neuroglia-fibres issuing from neuroglia-sheaths which have 
given rise to descriptions of multipolar ganglion cells. 
