Linda,

Opercula of Melongena corona, in the Archerd Collection, also have a
decidedly rough texture and are pointed. The shell shown is 6 cm and
was collected in the early '60s. Gladys Archerd was very careful about
preserving opercula with the shells.

<http://nighthawk.tricity.wsu.edu/museum/ArcherdShellCollection/
Gastropoda/Melongenidae.html>

-Burton Vaughan




On Thursday, July 24, 2003, at 09:01 PM, Automatic digest processor
wrote:

> From: Jim Miller <[log in to unmask]>
> Date: Thu Jul 24, 2003  2:09:05 PM US/Pacific
> Subject: Re: Operculum of Melongena corona
>
>
> Hi Linda,
>
> The operculums of Melongena corona can be quite varied, even
> within localized colonies, and certainly with widely scattered
> populations. It is very easy (once you get a feel for it) to recognize
> 'percs, even without the shell. Tulips have a very smooth 'perc,
> while M. corona has a somewhat rougher 'perc with distinct
> growth lines. Obviously, the size of the shell may be a factor,
> as well. Without seeing the "pointed ones" you are describing,
> I couldn't tell you if it's a mistake or just the way those shells
> grew their "doors."
>
> Jim
>
>
>> I was examining a lot of old shells (collected in the
>> 1970's) from Sanibel, some of which have opercula in them.
>> My problem - the Melongena corona I collected recently,
>> fairly small ones, have a rounder operculum than these old
>> ones.  Their opercula have a distinctive point, i.e., they
>> look more like Fasciolaria tulipa opercula to me.
>>