1 88 
Batters. — On Schmitziella , 
besiae, I found in that portion of the cell-wall of the Clado - 
phora which was situated immediately beneath them, some 
beautiful specimens of the endophyte, sterile it is true, but 
more richly coloured than specimens from unencrusted por- 
tions of the host-plant. 
How the spores of Schmitziella make their way into the 
cell-wall of the Cladophora is rather obscure, but still it is 
worth while taking the following circumstances into con- 
sideration. In the genus Cladophora the zoospores make 
their escape through a small aperture in the cell-membrane 
situated at the upper end of each cell just below the point 
where it is attached to the cell immediately above it. Now 
in C. pellucida the dissepiments of the cells are situated at the 
forkings of the branches and ramuli, and it is just at this spot 
that the young plants of Schmitziella make their appearance. 
It seems probable therefore that the spores of the Schmitziella 
get lodged in the axils of the branches of the host-plant — that 
is at a spot where either there is an aperture ready-made for 
them, or at any rate where, we must suppose, the membrane 
can be most easily pierced — and there germinate. Once 
having gained an entrance between the layers of the cell-wall 
of the host-plant, the endophyte grows very rapidly and 
spreads from cell to cell of it. I have traced the filaments of 
one Schmitziella plant through three of the very long cells of 
the Cladophora. 
The earliest stage in the development of the frond of 
Schmitziella that I observed consisted of seven very irregu- 
larly shaped cells (Plate X, Fig. 2). The spore appears to 
have divided into four parts, one of which has again divided 
into three. In the next stage observed, growth appears to 
have taken place in two directions (Fig. 3), the spore as in the 
former case having divided into four parts, the two central of 
which have again divided so as to form rudimentary lateral 
branches. After this stage the plant developes very rapidly, 
and the frond soon assumes the appearance represented in 
Fig. 5, in which it will be seen that the cells are arranged in 
a more or less filamentous manner ; but it is not till a later 
