優雅に向きを変える鞭毛虫 ; A gentle flagellate

Japanese commentary is followed by English commentary

前方の短い鞭毛を動かし、長い鞭毛を後ろへ長く引きずりながら優雅に向きを変える鞭毛虫。前方から近づいた珪藻を捕えたが逃げられる。

----- 月井雄二先生(法政大)のコメント -----
これはアニソネマ（Anisonema）です。
http://protist.i.hosei.ac.jp/PDB/Images/Mastigophora/Anisonema/index.html
２本の鞭毛を持ち，長い１本（後曵鞭毛）が後方に伸びて引きずるようにして移動するのが特徴です。

This flagellate has two flagella of different lengths at the front. The shorter flagellum vibrates intensively and the longer one curves around the side and extends far behind the body.A diatom caught by the shorter one got free soon .

----- Commentary by Prof. Yuji Tsukii, Hosei University -----
This flagellate belongs to genus Anisonema.
http://protist.i.hosei.ac.jp/PDB/Images/Mastigophora/Anisonema/index.html
The organism is characterized by two flagella of different lengths. When it moves, the longer flagellum trails far behind the body.