Paramecia are a group of unicellular ciliate protozoa formerly known as slipper animalcules from their slipper shape. They are commonly studied as a representative of the ciliate group. Paramecia range from about 50 to 350 μm in length, depending on species. Simple cilia cover the body which allow the cell to move with a synchronous motion (like a caterpilla). There is also a deep oral groove containing inconspicuous compound oral cilia (as found in other peniculids) that's used to draw… (More on Paramecium)