Phylum Porifera Grant, 1836 - sponges Class Demospongea Sollas, 1875 see Class Demospongiae Sollas, 1885 Subclass †Lithistida Schmidt, 1870 Order Axinellida Lévi, 1953 see Order Halichondrida Vosmaer, 1887 1 Family Axinellidae Carter, 1875 2 Family †Agelasidae Verrill, 1907 (1875)