152 BBAMBLES AND BAY LEAVES. 
parent, and the balance is restored. Monas, euglena, 
uvella, cryptomonas, gonium, and other wondrous in¬ 
fusoria, may be detected as constituents of the cloudy 
mass while it lasts, called into being because the con¬ 
ditions of the tank were such as they required; as if life 
in embryo was everywhere locked up until the moment 
came for its liberation, and some particular circum¬ 
stance was the talisman to set it free; or if we consider 
created forms to be marshalled in grand procession, may 
we not expect that every tribe will hurry to its appointed 
place the instant that a door is opened ? 
Microscopists have long been at war, but without 
bloodshed, as to the place to be assigned to certain 
organic forms which are hidden from our common eye¬ 
sight. While the war goes on as to whether desmidiacse 
and diatomacese be animal or vegetable, or both, let 
facts suffice us here in the study of the aquarium. Does 
an animal exhale carbonic acid? Yes. Well, here are 
plants or animals, concerned in keeping up the balance, 
which exhale oxygen, and their name is legion. Yolvox 
globator and the bacillarise labour as hard to supply 
the fishes with the life-sustaining gas as do the silken 
threads of verdure that line the glass like a carpet. Is 
the possession of starch a distinctive feature of the 
vegetable ? Perhaps so. Truly here are desmidiacse 
that contain starch, and if I make the possession of cilia 
the test for assigning certain forms to the animal king¬ 
dom, I find in the aquarium spores of algse furnished 
with them. Motion I know to be no test, because algse 
spores dance through the water gaily till they find a 
resting-place, and when the aquarium was first filled. 
