492 Farmer. — On Spore- Formation and 
of the reproductive cells, but almost equally well during the 
germination of the spores. 
At this period, that is, when the nucleolus is fragmentary, 
the longitudinal division in the linin thread is effected, but it 
is not easy to follow out the details owing to the obscuring 
effect of the nucleoli. The linin, which is now becoming 
increasingly rich in chromatin, swells up and finally breaks 
into eight chromosomes, but I could not at this time find any 
trace of the primary slit formed by the earlier longitudinal 
fission. The spindle is now formed, and the eight chromo- 
somes lie along it. They resemble the chromosomes of Lilium 
at the corresponding stage, and each one consists of a hump 
or thickening, directed outwards from the spindle, and two 
limbs which lie along it. When they have reached this stage 
they may in favourable cases be recognized as being of a ring- 
like form (Fig. 61), though this is often difficult to determine. 
Eventually they divide across the middle, and the two daughter- 
halves retreat towards their respective poles. A cell-plate is 
then formed across the equatorial plane of the spindle, but it 
remains in a rudimentary condition, and does not effect 
a division of the cell. The two daughter-nuclei immediately 
divide again, and so far as I could determine the question, the 
second division is here also exactly similar to the first, in its 
later stages at least. There is the less doubt in this case (as 
compared with Pellia ), since the normal vegetative mitoses are 
very different from those which we are now considering (cf. 
Figs. 70, 71). It must for the present be left an open ques- 
tion whether the second mitosis is prepared for during the 
formation of the young chromosomes for the first division. 
I failed to find any direct evidence for this hypothesis, though 
I especially looked for it. Sometimes, during the shortening 
up of the linin to form the chromosomes, a localization of the 
chromatin at four spots could be seen, but this did not occur 
with sufficient frequency to admit of any safe generalization 
being based on it. At the same time, a similar condition was 
sometimes observed both in Pellia and in Fossomhronia , as 
mentioned above. 
