354 BOTANICAL GAZETTE [NOVEMBER 
acceptance of the chromosome hypothesis by making it highly desir- 
able on theoretical grounds to find the material bearers of hereditary 
units which the law seemed to demand, that practically all opposition 
to it was swept away, and it has come to be the groundwork on which 
present-day cytology has been constructed. If then the basis on 
which the theory rests is in any degree unproven, it is well for cytolo- 
gists to keep that fact clearly before them, that they may be guarded 
against making any false steps in blind adherence to an insecure 
hypothesis or of failing to notice any evidence which might throw 
doubt on the validity of their theory. 
The writer for his own part, however, has no intention of discard- 
ing the whole hypothesis of chromosome individuality on the basis 
of these observations on Synchytrium, or on the similar results 
obtained by CuiLp (2) from studies of representatives of nearly all 
the great animal phyla. The conflict of evidence for and against the 
hypothesis seems clearly to require us to keep the case open for the 
present. It is as tending to promote such a judicial attitude of sus- 
pended judgment among cytologists rather than as overthrowing the 
whole theory that the writer would have his results received. 
Summary 
The mitoses are all of the same type and occur simultaneously 
throughout the cyst. 
The spirems of amitosis are frequently indistinguishable from those 
of mitosis. 
The spindle is of the oomycete type, without centrosomes. 
The asters first appear as emanations from the condensed chro- 
matic mass of telophase, but quickly separate from the chromatin 
and their rays form the nuclear membrane. » 
The number of chromosomes is constantly four. ; 
In some sorts of amitosis an equational division of the chromatin 
previous to the division of the nucleus is possible, though there is no 
evidence of such a process. 
In other varieties of amitosis an equational division of the chro: 
matin does not seem to be possible, but rather direct division gives 
some indication of being merely a physical process as suggested by 
CHILD. 
