Grinnellia americana , Harv . 
9 
beneath the cystocarps from which they come, while the 
tetraspores are promiscuously distributed in much less abun- 
dance over the bottom of the dish. A gelatinous secretion 
begins to form about both carpospores and tetraspores very 
soon after they pass into the water, which serves to protect, to 
hold the spores together, and to fix them to the bottom of the 
dish or other substratum. The fact that they immediately 
fall to the bottom of the containing vessel shows that they 
have a greater specific gravity than the frond, which is 
probably due to the fact that their chromoplasts and other 
contents are denser than those of the cells of the parent 
frond. 
In a few hours after the liberation of the carpospores they 
are so thoroughly fixed to the substratum by the gelatinous 
secretion, that it is necessary to subject them to the full force 
of a strong stream of water in order to loosen them. So 
far as could be determined by experiment, they become much 
more firmly attached than the tetraspores, which, in every 
case, are found to be easily detached from their position 
before germination. These phenomena lead to the belief 
that the special function of the asexual spores of Algae is 
identical with that of the asexual spores of Fungi ; viz. 
immediate distribution. The carpospores differ so little 
in colour and shape from the tetraspores, both being lake-red 
and elliptic-oblong, that they are scarcely distinguishable 
from one another. They agree closely in size, averaging 
30 /x by 50 ju, just preceding liberation. Shortly afterward 
they become more spherical and enlarge to 36 /x by 48 /x. On 
account of the densely aggregated chromoplasts in the newly- 
deposited spores, it is extremely difficult to distinguish the 
nucleus. However, when treated with five per cent, acetic, 
or one per cent, picric acid for ten minutes, washed thoroughly 
in distilled water, and then stained with Delafield’s haema- 
toxylin, the nucleus of each spore is readily recognized. 
