3 and ref. Stentor are one of the largest protozoa found in water, and is therefore one of the easiest for the microscopist to study. This article describes where you can find the Stentor and how different types of illumination under the microscope can be used to show the characteristic features of a protozoan. In the modern classification of organisms, the protozoa belong to the kingdom Protista along with the algae and lower fungi. The Protozoa are unique in that the single cell performs all the functions of feeding, digestion, excretion, respiration and reproduction.
Stentor are usually present in most freshwater ponds.
Take a few pieces of the stem of any floating plant eg Potamogeton, which has spear-shaped leaves. Place the stems in some water in a shallow dish and allow a few minutes for the water to settle. Stentor may also be swimming freely, when they become more oval in shape with a narrowing at their posterior. This leads in turn to an increase in the population of protozoa such as Stentor which feed on the bacteria. Colonies of Stentor often occur, in which the lower parts of the animals are covered with a mucilaginous substance which they secrete.