86 Church . — The Polymorphy of 
At one or more points in the ‘ Foot,’ any single super- 
ficial cell may initiate a new growth (Fig. 15), which, by 
successive T-shaped walls, gives a lobed outgrowth which 
exhibits dorsiventral symmetry, and by laying down the 
marginal segment-walls preferentially in a radial vertical 
plane, assumes a fan-shaped outline, the commencement of 
an Aglaozonia disc (Figs. 15, 19, 20). The formation of these 
lobes appears to be mainly due to the stimulus of contact, 
and thus a majority form discs at the point of attachment 
(Figs. 19, 22); but if the apex of the ‘Foot’ bends over, 
a symmetrical outgrowth may take place there, either alone 
or in addition to another at the base (Figs. 17, 18, 20). In 
the case of the foot lying more or less prostrate, several (6-8) 
distinct lobes may be produced, which develop rhizoids on 
the side towards the substratum (Figs. 20, 21). In plants 
which have become detached, the dorsiventral lobes con- 
tinue to be formed and exhibit a tendency to curl up, 
indicating a return to radial symmetry comparable to that 
of the proliferating ‘ cups ’ of Z anardinia. 
Although many distinct cultures were made, and hundreds 
of embryos observed, in no single case was any further 
development noticed in the ‘Foot’; the dorsiventral lobes 
slowly but steadily increasing along definite Aglaozonia lines. 
Following Falkenberg, this type of plant may suitably 
be distinguished as the Foot- Embryo. 
It will therefore be noted not only that these observa- 
tions on the development of the Aglaozoma-ths.\lus from 
oospheres of Cutleria absolutely confirm those of Falkenberg, 
but that such confirmation was necessary, since the embryos 
observed by Thuret 1 at Saint Vaast-la- Hogue in 1850 were 
unmistakably different : it was in fact the figure given by 
Thuret of a free-growing filament of thirty-six cells with 
branches towards the base, which appeared, as being a 
vegetative growth homologous with an adventitious branch, 
to confirm his assertion of the non-sexuality of the oospheres. 
1 Etudes Phycologiques, and Ann. Sci. Nat. iii. 14. 
