Dear Sarah;-
        I wrote this note before than hit the wrong button. Yes; E. turbinum is
very rare. We photographed it at ASNM. (or something like that). E.
pernobilis is not quite that rare. But rare enough and expensive enough
to evade my collection. What amazes me about them is that they are only
about an inch or so. They look much larger, what with all the wild
sculptering on them. Federico Sacco published a plate of Ep fossils.
There seem to have been a lot more Sts during the Miocene, Pliocene, and
other ---cene eras. Perhaps, like the Komodo Dragon, our turbinum and
pernobilis are "living fossils".
        Art