title: Part E, Porifera (Revised), vol. 4 &amp; 5, ch. 4, p. 209–292
abstract: lVi, 1953, Demospongiae, has diminished in the contemporary literature, as these groups have been recognized to contain polyphyletic taxa (hooPeR & Van soest, 2002b, p. 16-17). This has been confirmed by a recent analysis of the phylogenetic relationships of the orders of Demospongiae based on 18S and 28S rRNA (BoRchiellini & others, 2004); so these subclasses will not be used here.] ?Silurian, Middle Devonian-Holocene. Demospongiae
journal: Treatise on Invertebrate Paleontology