46 
The Ohio Naturalist. 
LVol. VII, No. 3, 
at others on the side where there is the least cytoplasm (Figs. 3 
and 4). There is again no uniformity in this respect. 
The variety of types of synizesis might be much increased 
but the examples given will make it plain that there is nothing 
uniform in the behavior of the chromatin in synizesis either with 
respect to the nucleolus or the nuclear cavity. Synizesis appears 
to be an artifact when considered from the standpoint of plas- 
molysis, but the question must be settled, if possible, through 
the study of living material. But if staining reagents are em¬ 
ployed, great precautions are necessary even with living material. 
At the present stage of the subject it seems useless to continue 
the investigations by merely giving conclusions from a set of 
preparations which may present a supposed series of uniform 
conditions. 
The results of this investigation may be briefly summarized 
as follows: The synizetic knot is not always around or in contact 
with the nucleolus but very commonly one may find it entirely 
distinct from the nucleolus. The chromatin is not always uni¬ 
lateral but very often central. If the knot is at one side it has 
no evident relation to the direction of gravity. Synizesis also 
does not mark the stage where the chromatin threads become 
homogeneous. In cases like Lilium tigrinum the chromatin 
granules, if properly stained, are seen at their best after the great¬ 
est possibility for contraction is passed. It seems from an inves¬ 
tigation of the literature of the subject that there has been much 
speculation and reporting on “uniform conditions” simply be¬ 
cause synizesis or “synapsis” has not been explained. But it is 
at present more important to discover the actual condition of 
things. The time at which synizesis occurs has not shown any 
uniformity. When one examines figures of this condition he is 
surprised at the lack of uniformity present. Some have even 
gone so far as to describe two “synapsis” stages before the for¬ 
mation of the mother star. During the early stages of division 
the nucleus is the seat of great chemical activity and the expan¬ 
sion of the nuclear cavity and changes in the chromatin network 
give rise to conditions which are especially favorable for the pro¬ 
duction of artifacts. 
After the chromatin thread becomes thicker the contrac¬ 
tions, as one would expect, are less common though by no means 
entirely lacking. Later when the orientation of the bivalent 
chromosomes begins, distortions are again abundant in many 
preparations. These series of distortions and contractions in¬ 
cluded under the term “synizesis” have at present no meaning 
and the mechanics of the process remains unexplained from the 
standpoint of a natural stage of karyokinesis. 
