DEGENERATION OF THE EGG-CELLS OF THE GASTROPODS. 
287 
The degeneration of the nucleus of the affected egg-cells begins, 
as a rule, by hypertrophy, though the degeneration very often proceeds 
without hypertrophic processes. Such hypertrophie nuclei are to be seen 
on fig. 4, Pl. YII (left side, below). The nucleoli of the hypertrophic 
nuclei are still more hypertrophied than the nuclei themselves. The 
nucleoli of the sound nuclei are relatively very small, those of the hyper¬ 
trophic ones, on the contrary, sometimes so large that they fill nearly 
the whole interior of the nucleus. 
Degeneration begun with hypertrophy and followed by atrophy 
was observed by other authors as well. R. Hertwig found in Adi- 
nosphaerium enormous chromatic and achromatic nucleoli. Brasil (2) 
observed such hypertrophic phenomena in the intestine cells of the 
Poly cheta Lagis coreni, and Ehrlich (7) in ihose of Ascaris. Léger 
and Dubosq (11) observed a similar process in the intestine epithelium 
of Tracheates which case is all the more interesting, since the degene¬ 
ration was regarded by the authors as a reaction set free by an in¬ 
fection of Gregarians, thus this case is very similar to that of the egg- 
cells of the Gastropods the degeneration of which was also caused by 
the intervention of foreign cells. 
The chromatic and achromatic substances of the nucleoli during 
degeneration separate from one another. The separation begins in the 
first stages of degeneration. The extremities are again represented by 
the hypertiophic nucleoli the chromatin of which restricts itself into a 
corner of the gigantic plasmosome (fig. 4, PI. YII). This pathologic 
separation of chromatin and achromatin was also observed by Ehrlich (7) 
in the degenerating intestinal epithelium cells of Ascaris. Together with 
the separation of both substances begins the transmigration of the chro¬ 
matin into the interior of the nucleus where it forms irregular clumps 
composed of small granules. During the later stages of degeneration the 
nuclear membrane gradually dissolves, and then the nucleus is marked 
only by a clear, more or less irregularly shaped spot in which some 
chromatin granules are to be seen (PI. YII, fig. 2). Later even 
this remnant of the nucleus becomes more and more restricted, its 
chromatin granules disappear, and degenerates the plasmosome as 
well dissolving in the cytoplasm which has also degenerated in the 
mean-time. 
The degeneration of the cytoplasm is characterized chiefly by two 
processes. The first one is that the outlines of the affected parts of the 
cytoplasm become indistinct, and thus the cytoplasms of the affected 
and affecting cells eventually unite (PI. YII, fig. 5), or, if more egg-cells 
L rm a group, they unite with one* another (PI. YII, figs. 2 and 4), the 
