Differential interference contrast (DIC) light micrograph of Radiolaria. Radiolaria are single-celled protozoans that are found in marine plankton. They have a silicate skeleton with pores through which pseudopodia of protoplasm project. As the animal floats in ocean currents the pseudopodia trap food particles on which the radiolarian feeds. Magnification: x120 when printed at 10 centimetres wide at its longest edge.