Pe ea Se 
1899] SPORE-MOTHER-CELL OF ANTHOCEROS 101 
features of the mitotic figures. There should be types of plants 
that will allow us to form some idea of the relationship between 
filarplasm and the asters and centrospheres present in certain 
thallophytes, in other words solve the problems of their places 
in phylogeny. Perhaps the future study of Hepatice will throw 
some light on this question. 
The two sets of daughter chromosomes that result from the 
division at metaphase pass very quickly from the nuclear plate to 
the poles of the spindle. Here they may frequently be found 
clustered together ina region of dense protoplasm that surrounds 
the group, as is shown in fig. ro. The development of a nuclear 
membrane around the chromosomes finally organizes the two 
daughter nuclei which are connected for a short time by the 
spindle fibers. These latter structures gradually fade away, 
beginning at the poles (fig. 20), and finally entirely disappear. 
The daughter nuclei then lie in undifferentiated cytoplasm usually — 
occupying positions between the chloroplasts somewhat as is indi- 
cated in fig. ar. 
. iy daughter nuclei following the first division pass into a 
eras developed resting condition. The chromosomes break up 
ss 3 number of chromatin granules that become distributed over 
rh network. A prominent nucleolus appears. In sections 
— one may always find spore-mother-cells con- 
ne elas nuclei, although this condition is quickly replaced by 
ceding second division. 
en ih mitosis in the spore-mother-cell involves both 
a but the two nuclear figures are developed 
by Ges ci y of one another. The two spindles are never united 
re ers. Sometimes the two spindles will lie almost side 
Y side, but usually they are placed igh les to each other. 
Frequently oe. y are placed at right ang - es ; 
1h OF bac... €ction of a spore-mother-cell will give a po ar . 
view of the a and the neighboring section a longitudinal 
‘js tg . se An instance of this character has been chosen 
in fig. > € principal features of their structure and is shown 
# By comparing fig. 24 with illustrations of the first 
- 16-18) it will be seen that the spindles of the 
