In the last few years there has been much interest in various physiological processes known to take place within toothed whales, dolphins, and porpoises (odontocetes). Such processes as respiration, audio-communication, echolocation, and buoyancy control have all been studied (Evans, 1967; Caldwell and Caldwell, 1968; Matthews, 1968; Poulter, 1968; Norris, 1968; 1969; Norris and Evans, 1967; Clarke, 1970). The odontocetes have been found to possess a large, fat-rich body called a “melon” in their foreheads, directly in front of the skull. It has been suggested that this melon is an acoustical transducer for transmitting and possibly focusing ultrasonic sound waves into the surrounding water for the purpose of echolocation (Norris, 1968; 1969; Norris and Evans, 1967). Certainly all odontocetes are known to produce orientated beams of sound, generated, it is thought, at the extermities of the animal's nasal plug (Evans and others, 1964; Norris, 1964).