A good, if somewhat outdated reference on echinoids is the Treatise of
Invertebrate Paleontology, volume U, Echinodermata (3). This is still in
print and available through the Geological Society of America's web site
http://www.geosociety.org  Another very useful reference is the Index
of  Living and Fossil Echinoids, Kier and Lawson, Smithsonian
Contributions to Paleobiology #34. Its out of print, but you might be
able to find a copy through a book reseller such as Naturama.

One of my favorite sites on the net related to echinoderms is the
California Academy of Sciences echinoderm links page at:
http://www.calacademy.org/research/izg/echinoderm/echilink.htm

Its wonderful to find other echinoderm lurkers on Conch-L. I have been
collecting and researching fossil echinoids and other echinoderms from
the Tertiary of the northwest coast of the US, and have started
collecting modern specimens to have on hand for reference. We have a few
unusual species in the fossil record here, such as a species of Salenia,
as well as a few important newly discovered species.

Regards,
Casey

--
Casey Burns - Wind Instrument Maker and Occasional Paleontologist
9962 Shorty Campbell Road  Kingston WA 98346 USA
(360) 297-4020
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