Dear Davids et al.,

Parasitic or not, these taxa are suspension feeders, and the strategic
position on the ventrum of the "host" gastropod shell ("crabbed" or with
living original inhabitant)
may allow better access to the material plowed up or otherwise suspended by
the larger, more active symbiont of the pair.

Harry


At 10:40 AM 1/18/00 -0500, you wrote:
>Some capulids and hipponicids are suspected of parasitism; the parietal
>area may be an easy spot from which to reach the host.
>
>In part, the preferential collection of nice-looking shells may be a
>factor.  Sabia does occur on other parts of the shell, but may either form
>an obvious flaw or, by making the shell appear plain and lumpy, camoflage
>it somewhat.  I think Gary's Encyclopedia of Seashells illustrates Sabia on
>the spire of a cerithid, although I do not have it handy to check.  The
>Southern Synthesis illustrates one on the spire of Conus.
>
>The Southern Synthesis cites two species of Sabia, S. conica and S.
>australis, as well as other genera.  It says that Sabia tends to occur with
>hermit crabs, so the parietal area would be a relatively sheltered spot as
>the shell is dragged.
>
>Dr. David Campbell
>
>"Old Seashells"
>
>Department of Geological Sciences
>CB 3315 Mitchell Hall
>University of North Carolina at Chapel Hill
>Chapel Hill NC 27599-3315
>USA
>
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>919-962-0685
>FAX 919-966-4519
>
>"He had discovered an unknown bivalve, forming a new genus"-E. A. Poe, The
>Gold Bug

Harry G. Lee
Suite 500
1801 Barrs St.
Jacksonville, FL 32204
USA   904-384-6419
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Visit the Jacksonville Shell Club Home Page at:
http://home.sprynet.com/~wfrank/jacksonv.htm

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