[Vor. 5 
216 ANNALS OF THE MISSOURI BOTANICAL GARDEN 
and that the majority of these spores were followed through 
their germination, both in mixed cultures and under control 
conditions, justifies one in the belief that there is no founda- 
tion for the idea that simply because biciliate and quadriciliate 
spores have been recorded іп Gomontia those possessing two 
cilia are gametes. 
GERMINATION OF ZOOSPORES 
The germination of the zoospore may occur in one of two 
different ways, there being no visible distinction between 
those which produce a vegetative filament direct and those 
forming resting spores which in the past have erroneously 
been regarded as akinetes or aplanospores. The direct ger- 
mination of a zoospore to produce vegetative cells was ob- 
served by Bornet and Flahault and regularly occurs in G. 
lignicola (pl. 13, fig. 4). Fully as many zoospores fail to ger- 
minate immediately, but after losing their cilia assume a 
spherical form and grow into a large irregular-shaped cell 
which ultimately produces, at from one to several points, vege- 
tative filaments (pl. 14, figs. 1, 5). Although the method of 
forming the mature thallus is, of course, different, this body 
may roughly be likened to the polyhedral cell formed by the zo- 
ospores of Hydrodictyon. The zoospores which develop into 
resting spores, instead of germinating directly, retain the red 
spot for several weeks and the process of growth into a ma- 
ture resting spore is a slow and gradual one. There is al- 
most as much irregularity in the ultimate size and shape of 
the resting spore as there is in the sporangium. Plate 15 gives 
some idea of the great diversity in form of these spores but 
there is no limit to the variety which might have been shown, 
since scarcely any two are of the same outline. These spores 
were the cells first found by me in examining the scrapings 
from the pine board, and it must be confessed that even after 
their origin was discovered they were suspiciously remi- 
niscent of certain unicellular grass-greens which have been 
described. 
The resting spores derived from zoospores are brilliantly 
green in color and full of starch. A single pyrenoid is plainly 
