metazoans Haeckel 1874 - multicellular animals see Kingdom Animalia Linnaeus, 1758 Bilateria Hatschek, 1888 - bilaterians see Subkingdom Bilateria Hatschek, 1888 Phylum †Proarticulata Fedonkin, 1985 Class †Cephalozoa Ivantsov, 2004 1 Family †Sprigginidae 2 Family †Yorgiidae Ivantsov, 2001