bilaterians Hatschek, 1888 - bilaterians see Subkingdom Bilateria Hatschek, 1888 Spiralia Schleip, 1929 - spiralians see Superphylum Spiralia Schleip, 1929 Mesozoa van Beneden, 1876 Orthonectida Giard, 1880 see Phylum Orthonectida Giard, 1880