Vertebrata Cuvier, 1812 - vertebrates Class Agnatha Cope, 1889 [paraphyletic] Subclass Cephalaspidomorpha see Class Agnatha Cope, 1889 1 Order †Osteostraci - osteostracans see Order Cephalaspidiformes 2 Order †Galeaspida Liu, 1965 see Order Galeaspidiformes 3 Order †Anaspida Traquair - anaspids see Class Anaspida Traquair 4 Order Petromyzontiformes Berg, 1940 - lampreys