SEXUAL REPRODUCTION OF THALLOPHYTES, OOD 
the Thallophytes, a few remarks may be made as to the 
indications which might be made use of for such a purpose. 
The Schizomycetes would appear to afford a starting-point. 
Those who advocate spontaneous generation will probably 
seize upon this as an important admission. Nevertheless there 
are good grounds for believing the doctrine which may be 
formulated as ‘ omne protoplasma e protoplasmate” Mr. 
Herbert Spencer is probably right in his conjecture that con- 
ditions once existed in which the interval between the che- 
mical combinations which obtain in the organic and the inor- 
ganic world might easily be passed, while now apparently 
they cannot be, or only with extreme difficulty. Under such 
conditions, matter doubtless existed in such states of spon- 
taneous aggregation as fitted it to subserve the nutrition of 
Bacteria. Now, we know that it only does so when derived 
from some organic source. 
The interesting observations of Professor Lankester, on 
Bacterium rubescens’ seem to show that we may pass without 
much difficulty from the Schizomycetes to forms belonging to 
to Chroococcacee, and other writers have also indicated their 
relationship to Oscillatoriee. From Chroococcacee we pass 
apparently through Palmellacee (Palmella cruenta), Pleuro- 
coccus, Confervacee (proper), Cidogoniee, Coleochetee, 
Nemalion, Floridee to Chara. This has been probably the 
course of the main line from which branches would be given 
off, which readily suggest themselves. ‘The earliest plants, 
supposing them to have been allied to Schtzomycetes, were 
therefore probably more like the Fungi than the Alge. And 
the food which is now furnished to Fungi from the organic 
world must then have been obtained from inorganic sources. 
Chlorophyll we may imagine to have made itsappearance when 
these pseudo-organic sources of nutriment ran short, and to 
have been seized upon by a kind of natural selection as soon 
as its power of promoting deoxidation in substances fitted for 
plant nutrition made itself manifest. 
Turning now to the forms from which chlorophyll is absent 
(Fungi), it must be remarked that notwithstanding the 
remarkable morphological parallelism which, as has been 
shown, they present at every step to the forms in which 
chlorophyll is present, it is still much more easy to connect 
them in a series with one another than to suggest, at present, 
the transverse links. It is interesting, however, to note the 
tendency of truly algoid types to assume a parasitic and con- 
sequently fungoid hfe. Reinsch finds that almost every large 
1 «Quart. Journ. Mic. Sc.,’ 1873, p. 408. 
