Polarised light micrograph of euglenoids and purple bacteria. Euglenoids are microorganisms are commonly found in freshwater. Instead of a cell wall, they are surrounded by a flexible proteinaceous covering called a pellicle. They possess the characteristic features of plants and animals. Many euglenoids are photosynthetic and have chloroplasts. However, they can also take nourishment from plant and animal matter, like animals. Purple bacteria are gram-negative proteobacteria that use photosynthesis to produce their own food. Magnification: 186x when printed 10 centimetres wide.