> Your lower left image also nicely demonstrates that the shell's early whorls
> are hyperstrophic (coiling towards the posterior end of the base), but at
> the beginning of the teleoconch the coiling becomes to orthostrophic. So,
> actually, the image is "upside-down". Did I get it right, Andrew G?
> See also: http://www.jaxshells.org/andrewg.htm
> Sincerely, Moshe Erlendur

Hi Moshe

I haven't looked at the image, but in a normal adult heterostrophic
shell such as Psilaxis the correct standard orientation is base
downward and protoconch upward (unless you're French, of course). If
you are illustrating an unattached hyperstrophic protoconch, or an
adult hyperstrophic shell (Lanistes, Limacina, abnormal Turbo or
architectonicid), then it should appear to be "upside-down", as the
"apex" is actually an everted umbilicus and thwe "base" is actually
the posterior surface of the whorls.

--
Regards
Andrew Grebneff
Dunedin
New Zealand
Fossil preparator
Mollusc, Toyota & VW van fan

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