The Southern Cassowary ( Casuarius casuarius ) , also known as Double-wattled Cassowary or Two-wattled Cassowary , is a large flightless black bird with hard and stiff plumage , two dangling red wattles and a big bony lump on its head called a casque . The Southern Cassowary , Casuarius casuarius , also known as Double-wattled Cassowary , Australian Cassowary or Two-wattled Cassowary , is a large flightless black bird .