Introduction to Porifera- This site describes the evolutionary history, life history, and ecology of the sponges. Many links to other sites are available.
Phylum Porifera- Information, from the University of Minnesota.
Phylum Porifera- University of Michigan site on phylum Porifera. Pictures, information on the phylum. Links to the four (some identify three) classes of sponges.
Porifera- Arizona's Tree of Life Web Page. Pictures, references, and information on sponges.
