A strange-shaped ciliate
The shape of this ciliate, Stokesia, reminds us of a ski cap or a bag. Although it stands perfectly still, the cilia surrounding its broad mouth are vigorously moving in an effort to stuck small food particles into the body.
Commentary by Prof. Yuji Tsukii, Hosei University
This organism is Vorticella
http://protist.i.hosei.ac.jp/PDB/Im.....
or Campanella.
http://protist.i.hosei.ac.jp/PDB/Im.....
Both organisms usually attached themselves to solid surfaces by an adhesive organ, but here the organism is floating.
From the structure of cilia around the mouth, the organism is likely to be Campanella.
Several particles and food vacuoles can be seen in the cell.
Sampling Date : 18 October 2009
Sampling Site : Hirose River A Google Map