Light micrograph of the head of a phantom midge larva (Chaoborus sp. ). Note the jaw-like appendages for capturing prey and the gas vesicles (tracheal sacs) used for buoyancy. Also known as the ghost midge or glassworm, the aquatic larval form of this midge is transparent. It preys on waterfleas and other small animals. Magnification: x21 when printed 10 centimetres wide.