Cetacean [def from Britannica Concise -ed.]: They are found in oceans worldwide and in some freshwater environments. Modern cetaceans are grouped in two suborders: about 70 species of toothed whales (Odontoceti) and 13 species of toothless baleen whales (Mysticeti). They have a tapered body, no external hind limbs, and a tail ending in a horizontal blade of two lobes, or flukes. Cetaceans must come to the water's surface to breathe through blowholes located on top of their head.50cent tie from the thrift store.