After an intense struggle, an euglena frees itself from a particle and swims around for a while. However it gets caught by another particle. It changes its flexible shape repeatedly in its effort to break free.
Commentary by Prof. Yuji Tsukii, Hosei University This organism is probably Euglena viridis.
Compared to the most common E. viridis, its body appears larger than usual, but such changes in size may occur depending on living conditions. The cell appears transparent and without particles in the rear half of the body. However, there are chloroplasts arranged like a ribbon along the cell wall to the rear end.
Here we can see nine Euglena cells that are completely still. Are they weakened, or have their sticky bodies become caught on the wall of the container? A small ciliate, Aspidisca, and a large slender ciliate pass nearby.
Commentary by Prof. Yuji Tsukii, Hosei University Various types of flagellates are included in the Euglena group.
Some species constantly swim actively, while others simply lie still
on the bottom surface.
A third type of flagellate exhibits both behaviors, alternately swimming
or staying still.
After stops moving, the organism often exhibits a simple round shape,
and the shape of its chloroplasts are difficult to distinguish.
This organisms looks like Euglena viridis, which can be seen at the following address.
Two single-celled flagellates, called Euglena, have become stuck on a solid surface and cannot move. When another Euglena joins them, it attaches itself to the first pair and stops moving as well. Meanwhile, various kinds of flagellates and ciliates are passing nearby.
Commentary by Prof. Yuji Tsukii, Hosei University The organism in the first scene is certainly Euglena viridis.
