Porifera

Khoyatan Sponge Page - Sponges of The Northeast Pacific - Photographs of four Classes of sponges in the Khoyatan Marine Laboratory.
http://mareco.org/spongepage/index.htm

Sponges: Porifera - Photographs and information on a number of species found around the coasts of Britain, provided by the Marine Life Information Network.
http://www.marlin.ac.uk/phylumdetails.php?phylum=2369

The Sponges of British Columbia - Descriptions of sponges by Curt Smecher.
http://www.interchg.ubc.ca/csmecher/sponge.htm

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

Underwater Field Guide to Sponges of Ross Island and McMurdo Sound, Antarctica - Beautiful annotated photographs of sponges (Porifera) of Antarctica.
http://www.peterbrueggeman.com/nsf/fguide/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

Sponges of Northern California Fouling Communities - Gallery of photographs of a number of species.
http://convoluta.ucdavis.edu/gallery/view_album.php?set_albumName=fouling-sponges

Phylum Porifera (Sponges) - Description of the sponges and their taxonomy, from the Animal Diversity Web.
http://animaldiversity.ummz.umich.edu/porifera.html

Halichondria bowerbanki - Photograph of this sponge and information including its identification, range and introduction into the US.
http://nas.er.usgs.gov/queries/FactSheet.asp?speciesID=1217

Porifera - Exercise from Invertebrate Anatomy OnLine covering the sponges, including Leucosolenia, Sycon, Spongilla, Cliona and Euplectella, in detail.
http://webs.lander.edu/rsfox/invertebrates/porifera.html

Sponge City - Article by William Amos on sponges and their general biology, and the pistol shrimp and other creatures that live inside their chambers.
http://www.microscopy-uk.org.uk/mag/artaug99/basponge.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.jiscmail.ac.uk/lists/PORIFERA.html

Nonindigenous Aquatic Species: Sponges - Species list from the USGS on the nonindigenous sponges found in US waters, with factsheets and collection details.
http://nas.er.usgs.gov/queries/SpeciesList.asp?Group=Sponges

Phylum Porifera - Illustrated information on the sponges.
http://www.meer.org/M27.htm

Porifera List - Links to a number of sponge-related sites.
http://www.jiscmail.ac.uk/cgi-bin/filearea.cgi?LMGT1=PORIFERA/