A drop of water sample was placed on slide and coverslip was placed over it. Spirostomum was observed under foldscope.
Spirostomum is a free-living ciliate protist, belonging to the class Heterotrichea. Species of Spirostomum are found in both salt and fresh water. All are elongated, flexible and highly contractile. The body of the cell is long and worm-like. It is mainly cylindrical but may be flattened at the tail end. A Spirostomum’s body has spiral rows of cilia. The cilia beat back and forth to move the organism with a snake-like wiggling motion. The mechanism of Spirostomum‘s contractility was first studied by Ernst Haeckel in 1873.
Spirostomum ambiguum can contract its body length by more than 60% within a few milliseconds. According to Dr Manu Prakash, they are very special since they can contract at an incredible speed(5ms); one of the fastest contractile cell.