Paramecium. Light microscope footage of ciliate protozoan Paramecium sp. The clip shows evacuation of waste from a food vacuole, and pulsation cycles of a contractile vacuole (red ring). This acts as an osmotic regulator, actively expelling excess water out of the cell. Paramecium are abundant in water and soil. They move by the rhythmic beating of many hair-like cilia, feeding mainly on bacteria. Filmed with differential interference contrast illumination.