David,
I observed similar behavior with a Pleurodonte lucerna in Jamaica
this past May.  The snail turned back on its shell and started to
seemingly chew up and down the lip of the shell from end to
end.  This went on all night.  Turns out it was adding to the shell
instead of chewing on it.  I'm wondering whether Eli was, in fact,
building up instead of destructing his shell?
Rich
~~~~~~~~~~~~~~~~~~~~~~~~~
www.worldwideconchology.com
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At 01:04 AM 8/21/2009, you wrote:
>Terrestrial lovers,
>
>Since finding two large live Mesodon normalis (see
>http://www.jaxshells.org/boonex.htm), my significant other has been
>keeping them in a terrarium. They've gotten lettuce, carrot, and fig
>for diet, plus some limestone and crushed oyster shell.
>
>This morning, I witnessed one of the snails (dubbed Eli) doubling
>back on him/herself and chewing on the area just behind its outer
>lip (and possibly a bit on the lip itself). This occurred for at
>least 10 seconds twice, accompanied by the light rasping sound that
>snails or slugs make which sometimes gets amplified enough to hear.
>
>Does anyone have knowledge of this behavior? Is this considered
>autophagy? [Or, since it's chewing on its exoskeleton, is this
>analogous to a human chewing on his/her own fingernails?] I didn't
>see any obvious marks on the shell. The snail has access to calcium.
>In fact, it was resting on a stone with barnacles on it.
>
>The snail seems healthy and right afterward stretched out fully to
>start chewing on fresh lettuce.
>
>David Kirsh
>Durham, NC
>
>"When you're chewing on life's gristle, DON'T grumble. Give a
>whistle!" --from Life of Brian
>
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