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Date: | Tue, 29 Jul 2003 08:57:08 -0400 |
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Dear Andrew;-
Good explanation.
Now---what is "inductural" and "ababical"?
"Q" Man
>
> From: Andrew Grebneff <[log in to unmask]>
> Date: 2003/07/28 Mon PM 05:17:31 EDT
> To: [log in to unmask]
> Subject: Re: Nomenclature
>
> >Hi, everyone!
> >
> >I need some help with several conchological
> >terms which appear to be used in different
> >ways in the literature.
> >
> >What is a "fossula"? I had thought it was a
> >vertical groove found on the inner lip of
> >cypraeids and ovulids. However, Liltved, in
> >"Cowries and Their Relatives of Southern
> >Africa", p. 34, refers to the fossula as a
> >"columellar depression" and the ridge next to
> >it as the fossula. Which is correct?
> >
> >Also, the terms "columella" and "base" appear
> >to be used in different contexts in various
> >publications. Some glossary definitions are
> >not clear. What is the difference?
> >
> >I look forward to your assistance.
> >
> >Conchologically yours,
> >Ron Noseworthy
>
> A fossa is a groove, NOT a ridge. A fossula is a small groove.
> Fossula I seem to remember being used for the depression produced by
> columellar inductural deposits in Cypraea and Trivia (should also be
> used for Erato and Willungia) and if present in ovulids too, and also
> possibly for the dorsal groove in Trivia?
>
> Columella is the lower (anterior, abapical) part, usually parallel
> with the coiling axis, of the labrum (inner lip); the part enclosing
> the umbilicus, if present; bounded by the parietal area posteriorly
> and the canal if present. In tightly-coiled shells it forms a solid
> core, prominent in logitudinally-sectioned shells. In
> siphonostomatous forms it forms the inner margin of the canal.
>
> Base is the lower (anterior or abapical) surface of a gastropod
> shell, which surrounds the columella; in Calliostoma it's the
> flattened bit the shell sits on if sat down upright. In most shells
> it's the part of the final whorl abapical of the periphery (widest
> part of the shell).
>
> In hyperstrophic shells what appears to be the columella and base are
> in fact NOT!
>
> --
> Regards
> Andrew
>
PLEASE NOTE: My new, long-term, and correct email address is: [log in to unmask] Please update your records!
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