W. B. Grove. 
176 
the vegetative division (see Fig. 7). The cell-division in the form¬ 
ation of the antherozoids is the same in detail as in the formation of 
daughter-coenobia, but the former can be carried a step farther, 
and differs, moreover, in the fact that the cells put out flagella at 
an early stage. Comparatively few bundles of 64 antherozoids, such 
as were seen at first, could be found on the later occasions. When 
the group of microgametes was formed from any one of the cells in 
the anterior half, the large original eye-spot could always be seen 
(still retaining its red colour) outside the group towards its base; 
rarely the two flagella belonging to the mother-cell of the group also 
remained unchanged outside the mucus. 
Colony 
Anterior 
Zone. 
Second 
Zone. 
Third 
Zone. 
Fourth 
Zone. 
Posterior 
Zone. 
1 
4 undivided 
4 antheridia 
4 coenobia 
8 coenobia 
8 coenobia 
4 coenobia 
2 
2 two-celled 
2 four-celled 
plakeas 
5 antheridia 
3 coenobia 
8 coenobia 
8 coenobia 
4 coenobia 
3 
4 eight-celled 
plakeas 
8 antheridia 
6 antheridia 
2 coenobia 
4 antheridia 
4 coenobia 
4 coenobia 
4 
1 two celled 
1 four-celled 
2 eight-celled 
plakeas 
8 antheridia 
7 antheridia 
l coenobium 
6 antheridia 
2 coenobia 
2 antheridia 
2 coenobia 
5 
2 four celled 
1 eight-celled 
1 sixteen- 
celled 
plakeas 
13 antheridia and 3 coenobia, the rest 
having escaped 
Since division always begins in the posterior end, it will be seen that (when 
antheridia and coenobia both occurred) the antheridia were the later formations. 
The period during which the antheridia occurred lasted about 
a fortnight; after that no more were found in the cultures, although 
further attempts at starvation were made. The statement made by 
Merton that the flagella of the mother-cell and its eye-spot always 
remain attached to the same daughter-cell is not correct with respect 
to either the antheridial or the vegetative divisions. On one occasion, 
in a young antheridial colony, a two-celled stage was found in which 
the beginnings of two flagella could be seen on the inner side of 
