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D? L. SOÓS 
second one is that its granular structure changes and it becomes re¬ 
placed by a particular granular-fibrous meshlike structure. The beginning 
of the transformation is to be seen on PL VII, fig. 5 (right side below), 
a more advanced stage is shown on figs. 4 and 2. The highest degree 
of degeneration is exhibited on text- 
figure 1 which represents such a case 
in which the degeneration has become 
complete without the intervention of 
phagocytes what also is a very frequent 
case. 
During degeneration the cytoplasm 
is generally the first to become decom¬ 
posed, the nucleus degenerating only 
in exceptional cases before the cytop¬ 
lasm (PL VII, fig. 2). From the parts 
of the nucleus first disappears the 
nuclear membrane which is followed 
by the decomposing of the chromatin, 
and the plastin resists for the longest time the action of the destructing 
agencies. 
In the literature many cases are known about the fibrous dege¬ 
neration of the egg-cells. According to Knoche (10) the cytoplasm of 
the egg-cells of Myelophilus piniperda transforms itself during degene¬ 
ration into a structure formed of wide meshes. Since Knoche has not 
given any figures of the processes observed by him, I have not the 
opportunity of comparing it precisely with that described in the pre¬ 
sent paper, but because some circumstances — to which I shall later 
refer — point toward the fact that the degeneration of the egg cells of 
Myelophilus piniperda is caused by the same factor as that of the 
Gastropods, it seems to me very probable that also the result of 
the process is the same. The degeneration of the egg-cells of Molge 
marmorata and M. palmata — as is shown by the researches of Pérez 
(16) — goes hand in hand with transforming of the cytoplasm into 
a fibrous-structured mass. The case described by Pérez is the more 
similar to that of the Gastropods, since the eggs of tritons are also 
destroyed by phagocytes, viz. by follicle cells transformed into pha¬ 
gocytes. 
According to my observations the nutrition of the egg-cells of the 
Gastropods never takes place through nutritive cells, but by means of 
diosmotic processes, as is seen on fig. 6, PL VII, which exhibits a nor¬ 
mal egg-cell of Planorbis corneus. ‘The granular substance visible in 
Helix arbustorum. Degenerated 
egg-cell. 
