McAllister—Cytology and Embryology . 
631 
that this stage occupies from % to % of the whole time con¬ 
sumed in the two reduction divisions,—from the first percepti¬ 
ble prophase of the first division to the telophase of the second. 
This observation accords in general with the observations of 
others in regard the duration of this stage. 
The commonly described loosening of the spirem begins at 
once at the close of the period of synapsis. We first find loose 
loops extending out into the nuclear cavity (Tig. pL ! 6). [Occa¬ 
sionally fine strands could be seen attached to these loops and 
connecting them with the nuclear membrane. Although the 
connections between spirem and the nuclear membrane are rela¬ 
tively infrequent in fixed material it is of course not impossible 
that in living material they are always present and that during 
the process of fixation they have been destroyed. These fine 
strands have been figured by Mottier, Berghs, Allen 
and other investigators for synapsis and the later prophases 
and they may also have some relation to the movements of the 
spirem, during the prophases of this division. 
As the spirem emerges from the synaptic condition it appears 
like a thick nodular filament, the nodules staining considerably 
darker than the main body of the filament ’(Tig. ,1*6). The 
nodules are not arranged in two parallel rows on the periphery 
of the spirem but seem to be located on all sides of the filament. 
The bodies on the flanks of the spirem, as observed from above 
are more conspicuous, while those lying on the upper or under 
surface of the spirem are less easily identified. The double 
spirem of the synaptic stage must have fused to form this single 
spirem, at some time in the later phases of synapsis. This 
stage with its scattered chromatic granules may represent a 
stage in which the fusion is still incomplete for later the spirem 
becomes homogeneous. 
After the spirem of the synaptic knot has begun to loosen it 
expands rapidly until it becomes uniformly distributed through 
the nucleus. (Tigs. 17 and 18). The spirem is at this period 
a uniform homogeneous filament showing no differentiation into 
chromatin and linin nor into chromomeres. The nodular ap¬ 
pearance apparent at first upon recovery from synapsis has dis- 
