The LED lights of the hand held microscope reflect on the water surface and bring out the colour of the branching gastrovascular system of Dendrocoelum lacteum. The white band in the middle of the body is the evertible pharynx, on one end of which is the mouth. Small organisms, including Water Slaters, are often prey of flatworms, and are subdued with the mucus and wrappen on the flexible bodies of the flatworm.
Richard Fitter & Richard Manuel 1986 Collins field guide to Freshwater life.
Helen Mellanby 1975 Animal life in freshwater life. Chapman & Hall.