160 BOTANICAL GAZETTE [FEBRUARY 
which neither of these writers was able to observe, would on this 
assumption be a distinct process. While it cannot be predicted 
that in the differentiation of the chromosomes Synchytrium will be 
found to resemble Rhodochytrium, it is clear that in the formation 
of the spindle there is considerable analogy. 
While the metaphases, and probably the prophases as well, of 
the second type of mitosis are similar to those of Synchytrium, this 
has no particular significance, since they present no peculiarities, 
but are similar to those of many other organisms. The telophases, 
however, differ considerably from those of Synchytrium, both in 
general form and in the absence of the conspicuous kinoplasmic 
asters, karyodermatoplasts, which in Synchytrium decipiens and 
S. puerariae form the nuclear membranes of the daughter nuclei. 
These structures remain, therefore, peculiar to these species. ° 
KaryoLympu.—The large primary nuclei, of course, are cut into 
several sections by the microtome. ~The central section of such 
a nucleus presents an appearance which would hardly be recognized 
by the uninitiated, for it looks at first sight like a hole in the 
cytoplasm of the parasite. It is surrounded, however, by the 
nuclear membrane and contains some of the amorphous masses of 
chromatin and perhaps a part of the nucleolus. But sometimes 
the whole nuclear cavity is filled with a frothy mass similar to that 
noticed by Kusano in Synchytrium after fixation with Keiser’s 
fluid. It appears to be, what Kusano interpreted it, a precipitation 
from karyolymph. I have not figured it because it is inconstant in 
occurrence and imperfectly understood. 
It should be noticed here, however, that the karyolymph may 
very likely play a much more important role in cell physiology 
than is at present assigned to it by cytologists. It is dismissed 
with a sentence in such texts as WILSON’s Cell, because our knowl- 
edge of it is practically nil. Yet, ignorant as we are, a little reflec- 
tion will convince us that it must be of some consequence to the 
cell. On the amount of karyolymph depends the size of the nucleus, 
for it is in reality merely a vacuole of karyolymph around which 1s 
stretched the chromatin reticulum. It is a well-known fact that 
by some means the size of this vacuole is maintained with slight 
variation in the cells of a given tissue. We know further that when 
