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Re: funny little green things
Dave Gomberg wrote:
>OK, more details. This stuff floats, sometimes as single blobs, but more
>often as clusters of 2-8 blobs and occasionally as tiny rafts of 10-20.
>Always on the surface, never in mid-water. The outside appears glistening,
>like a polysaccharide of some sort, so I would doubt it is ciliated. That
>would rule out Volvox???? And there does not appear to be any structure
>(stems, leaves, roots) so that would rule out Wolfia, right???? Each
>300-500u oval blob appears to be a cluster of 50 or so largish cells, with
>a slime coat. Does that sound familiar to anyone?
>
Volvox colonies are distributed throughout the water, not all up at the
surface. They may have up to 7 or 8 daughter colonies in them, but never
as many as 50. The individual cells of Volvox are too small to see without
about 100X magnification. These cells are all at the periphery of the
sphere, not in the interior. The cells are flagellated, and the sphere
swims slowly through the water. Wolfia doesn't have much structure left,
being sort of like a reduced duckweed that has lost its roots. What is
left is presumably some sort of combination of leaf and stem that looks
egg-shaped and solid green. Wolfia has no clear coating of jelly, and the
leaves, or whatever they are are water repellant and dry on top.
There is a cyanobacterium that consists of small cells in a jelly like
coating, but this species is very small, and you need at least 400X power
to even see the cells. It forms a green floculant-like mulm on the bottom.
There are some species of green algae that have a jelly capsule, but I
don't have a good book for identifying them.
Paul Krombholz, in central Mississippi where we havn't had any rain for
almost a month.