Phylum Porifera (Sponges) Description of the sponges and their taxonomy, from the Animal Diversity Web. http://animaldiversity.ummz.umich.edu/porifera.html
Hermit Crab Sponges An article by Floyd Sandford about the sponges that are carried around by hermit crabs. http://www.public.coe.edu/departments/Biology/hermit.html
Introduction to Porifera A good start on the biology of sponges, including phylogeny, life history, and ecology. http://www.ucmp.berkeley.edu/porifera/porifera.html
Porifera Biology on the WWW A central clearinghouse for sponge researchers, including a porifera listserver bulletin board and who's who in sponge research. http://www.mailbase.ac.uk/lists/porifera/files/
Phylum Porifera - 'Pore-bearing' animals Description of the phylum, including descriptions of its constituent taxonomic classes, with photos of a few representative species. http://www.teaching-biomed.man.ac.uk/bs1999/bs146/biodiversity/porifera.htm
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