176 W. WALDEYER. 
With regard to the position of the chromatic loops relative 
to the nuclear spindle we have seen already that the angles 
of the loops at the commencement are in great part inclined 
to the polar area, i.e. to the equator of the now obliquely 
placed nuclear spindle. When the spindle sinks so that its 
equator comes to lie nearer the middle of the nucleus, then— 
ang this is one of the chief figures of the last phase of the 
skein stage—the loops follow the equator of the spindle as if 
they were drawn down by it, and gradually group themselves 
in a ring round the equator with their angles inwards. It 
is evident, as Rabl points out, that with this the distinction of 
polar and antipolar areas ceases, and now two poles arise in 
the nucleus corresponding to the two poles of the spindle 
figure (see figs. 5, 6, 7). 
Two processes belonging to the final phase of the skein 
stage remain to be mentioned—the polar ray-formation 
in the cell-protoplasm, and the disappearance ofthe outer 
nuclear contour. 
The star figure (“Polar Strahlungen,” polar rays, “aster’’) 
in the cell-protoplasm has already been touched upon. In 
many cells, e.g. egg-cells, it appears very early, as Flemming 
has shown (58). In most cells, however, it first becomes dis- 
tinct at the final phase of the “ skein ;” the rays start from the 
pole of the spindle (figs. 7, 9, 10, 11). By all students of 
the subject it is agreed that the nuclear membrane becomes 
invisible towards the end of the “skein” stage. As to what 
happens to it the various opinions are not in agreement. Stras- 
burger has been the most occupied with this part of the 
process, and according to his idea, which has already been 
given, the cell-protoplasm enters the cavity of the nucleus on 
the disappearance of the nuclear membrane and here mixes 
with the nucleoplasm so that the original outline of the 
nucleus is completely lost, and there only remain as a material 
expression of the nucleus the chromatic threads and spindle 
figure. If, with Strasburger, we believe that the spindle 
figure is formed by the inflowing cell-protoplasm, then the 
formal nucleus from this stage onwards is represented only by 
